1994 530i rough idle, cylinder miss?

[Been-Jammin]

I just bought a cherry 1994 530i with 102k miles. It's running a bit rough, like a cylinder misfire at idle and low rpm acceleration. I replaced the spark plugs and added Sea Foam injector cleaner. The old plugs looked well seasoned with large white deposits and lots of dark carbon build up. The cylinders nearest the firewall had some standing oil around the spark plugs when I pulled them out.

I read that to check the engine codes, simply turn the key on (without starting) and depress the accelerator pedal 5 times within 5 seconds. I tried that several times to no avail. Can anyone tell me how to display the codes?

I was going to do a vacuum check and have been hard pressed to locate an exposed vacuum line. Does anyone know of any "easy to spot" vacuum leaks?

I read about the nikasil leakdown problems and hope the rough idle is unrelated. I haven't been able to get under the car to check the block serial number.

[dacoyote]

....up. The cylinders nearest the firewall had some standing oil around the spark plugs when I pulled them out. ...

That oil is from a leaky Valve Cover Gasket, it's easy to replace and doesn't cost that much if you DIY. The bad new is that you may ruined a coil or the DME. There isn't a really great way to test without swaping them out with good ones.


....I read that to check the engine codes, simply turn the key on (without starting) and depress the accelerator pedal 5 times within 5 seconds. I tried that several times to no avail. Can anyone tell me how to display the codes?
...

Thats how you do it... it's a PITA to get it to work (or at least for me)... you need to make sure the petal is hitting the kick down switch... some of the times it takes either slamming it really hard.. or just a nice set of five solid clicks



....I was going to do a vacuum check and have been hard pressed to locate an exposed vacuum line. Does anyone know of any "easy to spot" vacuum leaks?...

HAHAHAHAHAHA... sorry there mate, shouldn't laugh.. get out some carb cleaner... spray it arround and listen for the idle to change.

-Charles

[Been-Jammin]

1 725 970 - Nikasil block.

This explains the noticible roughness throughout the RPM range as well as the rough idle. Also explains why I could not find a vacuum leak. (there isn't one)

Does anyone know of any tricks to help keep this engine "alive" for a while? Should I try a heavier oil or additive to help "seal" the cylinder?

Also, has anyone done a block replacement on this model? If so, can this be done in a home garage by a DIY'r? Would I be better of taking it to a shop?

Thanks

[Tiger]

First thing first... get leakdown test done...

V8 engine roughness can be caused by bad ICV valve, leaky intake manifold gasket, and bad coil pack... all very common... especially the first two... which is usually done when it has about 100,000 miles.

I have nik engine too... still alive and very smooth.

[Kalevera]

Jammin my man.

Given that it has a rough idle, I'd say it isn't cherry then, is it...or is there something I'm missing? ;)

Now...if you haven't done so already, read Brett's article on the nikasil subject: http://www.koalamotorsport.com/tech-4.asp. He's already written many of the things I'd have to say on the subject. Mainly, that if it's working, no need to get in a tither about it getting worse.

"Rough idle" is a bit unclear to me. The cams in the M60 are responsible for some normal "roughness". And there's a fitted vacuum hose between the PCV plate and the FPR that, if loose or cracked, would result in a rough(er) idle. Beyond that, a compression test on each cylinder's the only thing that will confirm a block issue.

I completed my first alusil replacement a few weeks ago. It was routine, but I also do this for a living. A proficient tech can get the warranty job (if it still existed or applied) done in less than 8 hours (engine out, block replaced, engine back in). There are a few items, especially the transmission cooler, that I wouldn't want to deal with sans a lift and good tools.

EDIT: The other thing to note is that I see plenty of nikasil cars here in the midwest that are running just fine, many with 100k+ miles on them.


best, whit

[632 Regal]

read through barely nothing here... look into the spark plub boots and replace your intake gaskets...then go on to coils and crap. the boots and gaskets need replacing anyways...cant get into it now.

EDIT: PS intake leaks are notorius.


heath my advice.

[Been-Jammin]

First of all, thanks for the replies! All good information and appreciated.

I ordered a "leakdown tester" and will start there. But still want to be prepared for the worst. I'll order the plug boots.

I've read that there are common problems with the intake gaskets and PCV plate seal. That looks like a good weekend project. Is there a good way to check the condition of the ICV? (it's too expensive to just replace)

I took a closer listen today and will clarify that there is a noticible "miss" causing "roughness", like shaking. It can be heard from the tailpipe as well. Similar to pulling a plug wire, but quite as accentuated.

When the car warms up to a closed loop, the check engine light comes on and the engine practically dies (low rough idle, struggling to run) the ECU kicks in and RPM's go up briefly- kind of like a governor. After a few minutes the light goes out and it idles considerably better, but still feels as if it's dragging a cylinder. At higher RPM acceleration ( over 3500 RPM ) it is almost non-existent.

I'm having some serious issues doing the stomp test. Still haven't been able to get the codes to display. (irritating)

I've owned the same make and model before and remember that it wasn't exactly smooth at idle and "hard pull" low rpm acceleration. I just attributed it to a high compression, high cam engine and let it be. Put 70k of my own miles on that one with only a radiator, water inlet and brakes over 4 years. I used to pull a 5x8 enclosed motorcycle trailer without any problems.

As for my comment on the condition of this car being "cherry", it was referring to the physical appearance. ;O) The leather interior looks like new as well as the paint. It was owned by an old man, non-smoker. I have all the maintenance records, too. The O2 sensors were replaced at 90k 2 years ago, due to a "check engine light". There is no record of engine idle problems, nor a leakdown test. A year ago the air intake tube was replaced with the fan shroud during an oil change. The valve cover gaskets were replaced at 38k and 70k as well as the power steering hoses. There is still a reported leak, but nothing appearant under the car. I'll have to get a closer look.

All of this leads me to believe that there is hope that it is a coil, plug boot or PCV, ICV or even an Intake Seal problem, however I would still like to be prepared for the worst... In the mean time, it's still fun to drive the 5 speed. ;O)

[Been-Jammin]

read through barely nothing here... look into the spark plub boots and replace your intake gaskets...then go on to coils and crap. the boots and gaskets need replacing anyways...cant get into it now.

EDIT: PS intake leaks are notorius.


heath my advice.

Thanks! Here's the parts list: (for after the leakdown test) let me know if I'm missing anything!

8 Spark Plug Connector; Coil To Spark Plug; Updated Version 1.8kOhms
1 Intake Manifold Gasket; Front Intake Manifold to Throttle Housing
4 Intake Manifold Gasket; Intake Manifold to Cylinder Head
1 Intake Manifold Gasket; Rear Intake Manifold Cover O-Ring; 20x3.55mm
1 PCV Valve Grommet; Grommet for Ventilation Valve and Idle Control Valve

[Been-Jammin]

First thing first... get leakdown test done...

V8 engine roughness can be caused by bad ICV valve, leaky intake manifold gasket, and bad coil pack... all very common... especially the first two... which is usually done when it has about 100,000 miles.

I have nik engine too... still alive and very smooth.

Thanks! Is there an easy way to check the coil packs? I can get them for $48, but replacing 8 of them at once is a really bad day. Perhaps I should order one and just play swap 8 times. (or less)

[Bill R.]

intake manifold gaskets themselves, as far as vacum lines there really aren't that many, theres one cap on the backside as well as the line to the fuel pressure regulator that Whit mentioned. While the manifold is off, check these tubes for leaks at the back of the blockhttp://www.bimmernut.com/%7Ebillr/images/740manifold/740manifold10.jpg

A new pcv plate with new intake manifold gasket stuck on the bottom of the manifoldhttp://www.bimmernut.com/%7Ebillr/images/740manifold/740manifold11.jpg

And make sure you clean all the crap off of the intake manifold where it meets the head before you remove the manifold , otherwise dirt and stuff falls right into the intake ports and sometimes the cylinder... I scrub it out with a brush and a shop vacum.




Thanks! Here's the parts list: (for after the leakdown test) let me know if I'm missing anything!

8 Spark Plug Connector; Coil To Spark Plug; Updated Version 1.8kOhms
1 Intake Manifold Gasket; Front Intake Manifold to Throttle Housing
4 Intake Manifold Gasket; Intake Manifold to Cylinder Head
1 Intake Manifold Gasket; Rear Intake Manifold Cover O-Ring; 20x3.55mm
1 PCV Valve Grommet; Grommet for Ventilation Valve and Idle Control Valve

[Kalevera]

The other thing you should order is a few new bolts for both the PCV and the throttle body. They're Torx T30s and, let me tell you, they're a big pain to get out because they usually fuse themselves in there, especially after 11 years. Yes, it's illogical but a big pain, nonetheless. They'll probably strip out and have to be removed with vice grips. Put it back together with some antiseize grease (yes, I know the intake is plastic).

You're lucky it's a 5 speed. If the engine ever has to come out, you won't have to mess around with a trans cooler. That added a lot of time and expense to the job I did. Only thing is, good luck finding a 3.0 replacement block -- our boy Sajen's been on the prowl for one with no luck, TMK (did he ever find one?!)

best, whit

[Kalevera]

Also, be sure to get a code reader on the thing before you do ANYTHING...even a compression test. If the DME knows something's up, might as well know that before taking a shot in the dark.

best, whit

[Tiger]

Add valve cover gasket to your list... don't forget 8 orings for the plug holes.

[Been-Jammin]

Updated Parts list: (thanks to Lowell and Bill R.! )
BTW- I really appreciate the pictures!

8 Spark Plug Connector; Coil To Spark Plug; Updated Version 1.8kOhms
1 Intake Manifold Gasket; Front Intake Manifold to Throttle Housing
4 Intake Manifold Gasket; Intake Manifold to Cylinder Head
1 Intake Manifold Gasket; Rear Intake Manifold Cover O-Ring; 20x3.55mm
1 PCV Valve Grommet; Grommet for Ventilation Valve and Idle Control Valve
Added to the parts list:
1 Valve Cover Gasket Set; Left - Cylinders 5-8 (inner & outer)
1 Valve Cover Gasket Set; Right - Cylinders 1-4 (inner & outer)
22 Valve Cover Grommet Gasket; Valve Cover Nut Seal
1 Intake Manifold Cover (Rear PCV Plate)
1 Intake Manifold Gasket (at Rear PCV Plate)
Total: ~$200.00

I've already installed the Bosch 4417 Platinum +4's.

I didn't see the "O" ring Valve Cover Grommet Gaskets, would have completely over looked them, thanks Lowell for adding that in! Wow, 22 of them.

FYI- I'm ordering everything except the PCV Plate from autohausaz.com, the PCV Plate & gasket is coming from bmwwholesaleparts.com and it's labeled as an : "Intake Manifold Cover ".

[Been-Jammin]

On a cold engine, idling, A/C off, I sprayed the Throttle body where it attaches to the intake, then sprayed all around the intake covering every place along where it seals.

There was an instant idle increase when the carb choke cleaner first hit the throttle body gasket area. Idle returned to "normal" (still rough). No change for everywhere else I sprayed. Emptied an entire can.

I drove for about 11 miles and with and with a hot engine, sprayed everything again. No change in idle while spraying. However I did notice a significantly smoother idle all around. Still skipping a beat in the exaust rythm regularly enough to shake the car.

I did notice a loud "Whistle" while under the hood. Sounded almost like a turbo spooling up when I twisted the throttle body open and the engine revved up. There is also a loud constant "sucking" sound coming from somewhere around the intake. Spraying it with cleaner & didn't affect it at all. I spun the throttle body and as the engine revved, the "sucking" faded and the "whistling" took over. This leads me to believe that there might be a leak.

Not sure of the conclusion, except it's enough for me to replace all the gaskets/seals & PCV plate. The ICV will be a last resort due to it's price tag...

I'm going to try another test, by removing the oil cap/dipstick to see if the "sucking" sound or the "whistle" are affected. Will post the results shortly.

[winfred]

the o-rings are on the 6 cylinder, the v8 just has a smaller gasket that rings the whole plug area and comes with the valve cover gasket, 11 rubber grommits per valve cover for each nut don't come with the gasket kit but they should, they are what actually applys pressure to the valve cover and reusing the old ones can cause problems with possible leaks


I didn't see the "O" ring Valve Cover Grommet Gaskets, would have completely over looked them, thanks Lowell for adding that in! Wow, 22 of them.

[Been-Jammin]

I started it up, AC off, at idle I removed the dipstick and the oil filler cover. Left it loose as to prevent "oil fling" from the timing chains. When I twist the throttle, I can hear a pronounced "whistle" coming from the rear of the engine while it's revving up. There is no idle difference with the cap/dipstick out vs. installed properly. The "whistle" is a short, turbo spooling type sound. It's brief and happens only when increasing the RPM's.

Is this normal or an indication of a PCV failure?

Thanks!

BTW- I did clean out the dipstick seal as well as all the corrosion where the oil cap seals. What's with that nasty gold left over fried egg like stuff anyway?

[632 Regal]

After you replace (or before) the gaskets reboot the thing. When my intake was leaking last winter it ran just like yours, check light, the miss, everything. I rebooted the computer and it read that the leak was a "normal" leak and the car ran a lot better for several months until I got to the gaskets. When I had my intake off there was one of them air horns rolling around in there and that could have caused the intermittant miss by blocking an intake port.
Before that after I bought the car it had a real bad miss that I chased with coils, plugs, Injectors only to have the same miss which was "Caused by Nikasil" until I replaced the plug boots...they all checked out with the ohm meter but the new ones solved the whole dilema...40k or so ago.
Also, them specialty plugs can cause strange idle/miss problems, stick with the stocker plugs.
Good luck to you!

[Been-Jammin]

Also, be sure to get a code reader on the thing before you do ANYTHING...even a compression test. If the DME knows something's up, might as well know that before taking a shot in the dark.

best, whit


I've tried the stomp test a few times to no avail, but will keep trying as I would really like to see what the codes are. I think the local auto parts store has a diagnostic code reader and will test for free... time to find out.

[winfred]

whistle is not normal, the crud on the cap/dipstick is somewhat normal, i think it's a mixture of old oil and condenced and dried comtaminates from the oil, it seems to only really show up on the newer motors, m20/30s don't seem to do it, they will show a gooey sludge if not maintained and not the dried powdery **** of the m42/50/60 type motors

[winfred]

they probably don't have a bmw reader, a regular code reader won't touch a pre obd2 (95 and older) bmw


. I think the local auto parts store has a diagnostic code reader and will test for free... time to find out.

[Been-Jammin]

After you replace (or before) the gaskets reboot the thing. When my intake was leaking last winter it ran just like yours, check light, the miss, everything. I rebooted the computer and it read that the leak was a "normal" leak and the car ran a lot better for several months until I got to the gaskets. When I had my intake off there was one of them air horns rolling around in there and that could have caused the intermittant miss by blocking an intake port.
Before that after I bought the car it had a real bad miss that I chased with coils, plugs, Injectors only to have the same miss which was "Caused by Nikasil" until I replaced the plug boots...they all checked out with the ohm meter but the new ones solved the whole dilema...40k or so ago.
Also, them specialty plugs can cause strange idle/miss problems, stick with the stocker plugs.
Good luck to you!

Silly Question: How do I "reboot" it? Do I disconnect the battery? (I have the radio codes) I know the battery is located under the rear seat, but honestly, I've never seen it for myself.

[winfred]

you can unplug the computer which is under the black cover on the right side under the hood and not effect the rest of the car, the engine computer should be the one closest to the windshield, unplug for a minute or so and it's done


Silly Question: How do I "reboot" it? Do I disconnect the battery? (I have the radio codes) I know the battery is located under the rear seat, but honestly, I've never seen it for myself.

[Been-Jammin]

whistle is not normal,

Good to know.
PCV Plate/Gasket, etc. on the parts list... Thanks!

[Been-Jammin]

I shut off all of the accessories including radio and turned the AC vent controls all to the left. Pulled the key out entirely, put it back in and 5 stomps on the accelerator. The check engine light blinked, stayed on and then went into a pattern: .5 sec on, 2.5 sec off, 2.5 sec on, 2.5 sec off. It just kept repeating that exact pattern. I then held the pedal down for 10 seconds. Turne ignition off and repeated. This time it showed 1444. All Ok.

So will wait until tomorrow morning and see if the check engine lght comes back on and check the codes after that.

[Kalevera]

Ah, I'd still take it to a good indy and have them stick it on a machine. If the check engine light was ON, there's a stored code.

http://www.iaibmwsp.org

There should be someone in there who can read the codes for you. Local auto parts stores...hehe...well, they're usually a bad place to go for anything BMW.

best, whit

[632 Regal]

any vacumme related ill effect will result in the O2 code...which is irrelivant at this time. Either pull the computer out of the box or disconnect the battery for like 30 minutes...there is Shoguns reset which involves crossing the cables (after disconnecting them of course) and discharges everything, that seemed to make a greater difference than just disconnecting them.

[Been-Jammin]

any vacumme related ill effect will result in the O2 code...which is irrelivant at this time. Either pull the computer out of the box or disconnect the battery for like 30 minutes...there is Shoguns reset which involves crossing the cables (after disconnecting them of course) and discharges everything, that seemed to make a greater difference than just disconnecting them.

Thanks! I disconnected the computer, which no doubt cleared the codes. It's showing 1444 now. The check engine light only comes briefly when warming up and first hit's the "closed loop" coming out of "warm up" mode. Will have to see how it does in the morning and go from there. I took a 1/2 hour drive this afternoon and nothing unusual, no engine light either.

I've ordered all the intake gaskets, etc. including plug boots so should have a nice weekend project coming up. I'll have the leakdown tester by then as well. I figure it's worth it at this age/mileage if nothing else to clear my head of worry.

[632 Regal]

Does it still have the miss or did that smooth out some?

Is there a code from the CEL during warm up?

1444 = no codes

[Been-Jammin]

Does it still have the miss or did that smooth out some?


No change in roughness, idle or running. Still has a miss...
Going to check for codes in the morning after the drive to work.

[Been-Jammin]

Does it still have the miss or did that smooth out some?

Is there a code from the CEL during warm up?

1444 = no codes

Still running rough, but there was no check engine light today...

[632 Regal]

your computer thinks it supposed to run with all them leaks and stuff...Did any of the plugs look a lot different than the others?

[Been-Jammin]

your computer thinks it supposed to run with all them leaks and stuff...Did any of the plugs look a lot different than the others?

They were all about the same, the NGK's I pulled out looked aged on the outside and the nodes were covered with thick white deposits over a carbon build up. The two closest the firewall seemed a bit darker.

The tailpipe is nice and clean, no black deposits to the touch.

[632 Regal]

id still vote gaskets...no fear man!

[infinity5]

the suspense is killing us man, give us the results of the leakdown test!!!!

[Tiger]

IMPORTANT!!! Remove Bosch 4417 Platinum +4. BMW do not like them at all... Reinstall factory standard plugs.

[Been-Jammin]

IMPORTANT!!! Remove Bosch 4417 Platinum +4. BMW do not like them at all... Reinstall factory standard plugs.

Thanks! I know how cars can be picky about plugs. I appreciate the insight.
I'll pick up a set of Bosch F7LDCR's for this weekend's project work. Going to have them out to do the compression and leakdown tests anyhow.

[Been-Jammin]

I've ordered all the parts that I previously listed as well as an oil filter for good measure. They have all been shipped today and will be in Friday (if UPS is on time)

Here's the plan for this weekend: (taking photos)
1. Compression Test (check each cylinder's compression)
- If any are below 145, prepare for the worst, hold my breath.
2. Leakdown Test (check each cylinder for valve/cylinder leak)
- If results are really bad, turn purple, stop and prepare for a new block (save the new parts for the rebuild. )
- If results are marginal or above, continue (exhale and commense last ditch effort)
3. Replace valve cover gaskets/bolt grommets
4. Replace Intake, PCV and all associated gaskets/grommets
5. Install New OE Spark Plugs / New Plug Boots
6. Say a prayer (very important)
7. Start, warm up, test drive, check for any engine codes.
- If successful, do the "happy dance" in front of all the neighbors letting out a Woo Hoo that makes them all wonder about living in my vicinity.
- If unsuccessful, go do some burn outs in the church parking lot, maybe give my x a lawn job and test the rev limiter. Steel a jug of holy water from the church and top off the coolant reservoir. Pray for immaculate compression.
8. Change oil, drink a beer, relax by the pool for a few, get a sunburn, forget about the car for a while. Enjoy unmarried life a bit.
9. Download pictures from the camera, nurse my sunburn and post the results. May be Sunday by then...

[632 Regal]

before your panties bunch up so far that they constipate you read this:

If a cylinder is missing it isn't operating correctly (duh) and as so it wont have the same sealing characteristics as the cylinders next to them..as in oil hold out on the cylinder walls, rings and stuff. So dont totally freak...there is NO ****IN WAY i would want to know the leakdown on my perfectly fine running Nikasil block. It's when peroblems rear their head they can and do look worse when scientificly testing without a norm...such as all cylinders firing cause of leaks etc.

In the old days I used to buy peoples hydraulic cammed engines day after day cause of compression related falures :IE the lifters would collapse from the valve spring preload resulting in at least a couple weak cylinders.

May the force be with you!

[Gayle]

I've ordered all the parts that I previously listed as well as an oil filter for good measure. They have all been shipped today and will be in Friday (if UPS is on time)

Here's the plan for this weekend: (taking photos)
1. Compression Test (check each cylinder's compression)
- If any are below 145, prepare for the worst, hold my breath.
2. Leakdown Test (check each cylinder for valve/cylinder leak)
- If results are really bad, turn purple, stop and prepare for a new block (save the new parts for the rebuild. )
- If results are marginal or above, continue (exhale and commense last ditch effort)
3. Replace valve cover gaskets/bolt grommets
4. Replace Intake, PCV and all associated gaskets/grommets
5. Install New OE Spark Plugs / New Plug Boots
6. Say a prayer (very important)
7. Start, warm up, test drive, check for any engine codes.
- If successful, do the "happy dance" in front of all the neighbors letting out a Woo Hoo that makes them all wonder about living in my vicinity.
- If unsuccessful, go do some burn outs in the church parking lot, maybe give my x a lawn job and test the rev limiter. Steel a jug of holy water from the church and top off the coolant reservoir. Pray for immaculate compression.
8. Change oil, drink a beer, relax by the pool for a few, get a sunburn, forget about the car for a while. Enjoy unmarried life a bit.
9. Download pictures from the camera, nurse my sunburn and post the results. May be Sunday by then...


With a plan like that the mysterious forces of the universe will have to smile on you. Please have someone there to video the happy dance.

[infinity5]

"immaculate compression"
aaahahahahahaha :)

[Been-Jammin]

F 190 205 210 215 |
R 1* 2* 3* 4* |
O |Firewall
N 5* 6* 7* 8* |
T 215 208 205 210 |

The valve covers are riddles with this nasty coating looks like what used to be some kind of coating. They are going to get dropped off at the powder coaters in the morning. With any luck they will be ready by Thursday.

Leakdown test posponed to next week, UPS is now predicting Sept 6th.
Going to R&R the intake tomorrow, the intake seals & PCV came in early.

I don't have a Bentley yet, so any technical information is greatly appreciated.

Here's a pic of the valve covers: (YUCK)

[infinity5]

yep. thats what comes on the valve covers from the factory. Whatever it is is comes off and turns yellow and looks terrible. I kept meaning to get my VC's powder coated but i kept putting it off and now i don't have the money.

[infinity5]

Been-jammin, If you don't mind my asking, where in "noth east florida" do you live? my home town is gainesville and right now i'm in school down in Tampa.

[Been-Jammin]

Been-jammin, If you don't mind my asking, where in "noth east florida" do you live? my home town is gainesville and right now i'm in school down in Tampa.

I'm in Jacksonville, near the beach. Been here almost two years. Hometown is Hoffman Estates, IL just outside Chicago...

[632 Regal]

dude, you DO NOT HAVE NIKASIL FALURE!!!!!]
compression tests are read.
You have a healthy baby girl that needs some simple attention!
Congratulations man!

[winfred]

yea id say that's going to be good to go, i suspect a good quanity of the dealer diagnosed dead nik's were not a bad block but a pissed off computer and some sort of running problem that started it, i've seen and fixed it

[Kalevera]

Actually, they don't look *that* bad. And they were coated with some kind of paint or primer from the factory....it's simply burnt off with time.

The stuff is called cosmolene. Really a pain in the ass -- we had a practically new euro delivery M3 in a few days back and they sprayed it on the underbody, as most car manufacturers do (only with BMW getting cheaper in their ways these days/starting to chevrolize everything, it seems to be taking the place of the classic underbody protection stuff). It was hard to tell whether the underbody was covered in cosmolene or the result of an oil leak.

best, whit

[Been-Jammin]

Actually, they don't look *that* bad.

best, whit

There's a great powder coater here in town that I was hooked up with a year ago. He's done the entire engine compartment on my Mercedes and almost all of my race bike. We'll see what he can do with these. I'm going to have him coat them "black asphalt" which is a highly durable textured finish. It appears that the metal is fully intact and only the coating is fubar. Once they are bead blasted, we will know for sure. I'll post pictures when I get them back. (hopefully Friday)

[Been-Jammin]

yea id say that's going to be good to go, i suspect a good quanity of the dealer diagnosed dead nik's were not a bad block but a pissed off computer and some sort of running problem that started it, i've seen and fixed it

I'm quite pleased with the results.
A little concerned with the #1 cylinder, though...

Does anybody know the BMW acceptable tolerances for compression?
(I did look online, but have not found any technical specs yet and the Bentley is on order..)

[Kalevera]

15% on the leakdown, according to Brett. Not sure on the compression spec. The nik block I pulled out was down to ~ 92 on one cylinder and the thing didn't start (some of the others were lower, too).


best, whit

[callen]

I've got a 530 with about 160K miles and the the valve cover is deteriorating....metal turning to mush and crumbling away. Did paint and it looked better but just for a short while......point is, hope your powder coating isn't costing you too much ....it may flake off real soon.

[Bill R.]

deviation between cylinders.. I wouldn't get concerned at 160 if they were all pretty close to equal.. The normally allowed variation between cylinders is 10% max.. but i wouldn't worry about yours, I'm almost postive if you repeated the test a couple of times the cylinders would come out more equal. As Whit said 15% is the max leakdown but with your compression numbers i see no reason to run a leakdown test. Did you do a wet and dry compression test?






I'm quite pleased with the results.
A little concerned with the #1 cylinder, though...

Does anybody know the BMW acceptable tolerances for compression?
(I did look online, but have not found any technical specs yet and the Bentley is on order..)

[Been-Jammin]

deviation between cylinders.. I wouldn't get concerned at 160 if they were all pretty close to equal.. The normally allowed variation between cylinders is 10% max.. but i wouldn't worry about yours, I'm almost postive if you repeated the test a couple of times the cylinders would come out more equal. As Whit said 15% is the max leakdown but with your compression numbers i see no reason to run a leakdown test. Did you do a wet and dry compression test?

I did a "with fuel" test. I left the fuel pump hooked up and took out all of the spark plugs. I ran through 1-8 turning over each 15 revolutions. Started over, ran the test again. I re-ran the test on the #1 cyl about 4 times and each time was the same with the lowest reading at 185. 10% tells me that a reading of 190 is marginally acceptable and well within overall compression tolerance.

Typically with V8 engines the front cylinders get the most wear as they operate at an angle with less oil than the rear cylinders. This seems to have held true with this model.

[Bill R.]

don't check it with the throttle open you'll get a lower reading. And i would do a dry compression test and a wet one with a tablespoon or so of oil squirted down the plug hole.. if you get a big variation from dry to wet then it indicates rings rather than valve sealing.. Edit, fuel sprayed into the engine without it firing will tend to wash the oil off the cylinder walls changing your compression reading also..





I did a "with fuel" test. I left the fuel pump hooked up and took out all of the spark plugs. I ran through 1-8 turning over each 15 revolutions. Started over, ran the test again. I re-ran the test on the #1 cyl about 4 times and each time was the same with the lowest reading at 185. 10% tells me that a reading of 190 is marginally acceptable and well within overall compression tolerance.

Typically with V8 engines the front cylinders get the most wear as they operate at an angle with less oil than the rear cylinders. This seems to have held true with this model.

[Been-Jammin]

don't check it with the throttle open you'll get a lower reading. And i would do a dry compression test and a wet one with a tablespoon or so of oil squirted down the plug hole.. if you get a big variation from dry to wet then it indicates rings rather than valve sealing.. Edit, fuel sprayed into the engine without it firing will tend to wash the oil off the cylinder walls changing your compression reading also..

I agree, that is a much more accurate method. I'll put it to use.

Is there a simple way of disabling the fuel pump? (like a fuse or relay?)
Would simply disconnecting the fuel injection harness stop fuel flow to the cylinders?

Thanks

[Bill R.]

passenger side you'll find all the modules, the fuel pump module will be there in a row with 3 others, these are the small square modules.. closest to the passenger side fender is the o2 sensor relay, then comes the engine module relay, then comes the secondary air pump relay and the closest to the engine is the fuel pump relay. You can unplug all 4 if you want to if your not sure which is which ,just keep track of the color and put them back in the correct order.







I agree, that is a much more accurate method. I'll put it to use.

Is there a simple way of disabling the fuel pump? (like a fuse or relay?)
Would simply disconnecting the fuel injection harness stop fuel flow to the cylinders?

Thanks

[Been-Jammin]

Valve covers are done and look nice. A textured semi satin black.
Does anybody have the torque specs for the valve cover and intake?

I started with 10ft lbs on the valve covers. Went around with every other bolt until they were all snug, then torqued them to 10...

I'll be pulling the intake here shortly. That harness is a mess.

Thanks!

[Bill R.]

this translates to 10nm =7.37 ft.lbs 15nm=11.06
On the intake manifold any m8 bolts take 22nm=16.2ft.lbs and the other bolt, such as the 6 and 7mm are the same values as listed above





Valve covers are done and look nice. A textured semi satin black.
Does anybody have the torque specs for the valve cover and intake?

I started with 10ft lbs on the valve covers. Went around with every other bolt until they were all snug, then torqued them to 10...

I'll be pulling the intake here shortly. That harness is a mess.

Thanks!

[Been-Jammin]

I found a cracked vacuum hose that goes to the brake booster, a cracked vacuum hose cap that goes to the PCV and the fuel injectors are AFU, covered with crap. One of them was really clogged. The intake is soaked with oil, infact when I pulled the PCV, oil leaked out. YUCK. Nothing too crazy on the tear down, just lot's of little things to be unhooked and pulled out of the way. The aluminum tube underneath was pretty sneaky. No "horns" in the intake on this model.

Time to pull out the parts washer and go to town on the intake... Meanwhile, lunch, it's 90+ outside and I just lost my shade for the day, so may have to wait till the late afternoon to start the re-asembly. I wish I had a two car garage again... :(

[Bill R.]

bright flashlight and shine it down each intake port and look to see if any garbage fell into the port or if the valve is open into the cylinder, can cause some damage if not removed. I posted earlier about using a shop vac to suck up everything around the base of the manifold before you remove it to keep this from happeninghttp://www.bimmernut.com/%7Ebillr/images/740manifold/740manfold9.jpg









I found a cracked vacuum hose that goes to the brake booster, a cracked vacuum hose cap that goes to the PCV and the fuel injectors are AFU, covered with crap. One of them was really clogged. The intake is soaked with oil, infact when I pulled the PCV, oil leaked out. YUCK. Nothing too crazy on the tear down, just lot's of little things to be unhooked and pulled out of the way. The aluminum tube underneath was pretty sneaky. No "horns" in the intake on this model.

Time to pull out the parts washer and go to town on the intake... Meanwhile, lunch, it's 90+ outside and I just lost my shade for the day, so may have to wait till the late afternoon to start the re-asembly. I wish I had a two car garage again... :(

[Been-Jammin]

bright flashlight and shine it down each intake port and look to see if any garbage fell into the port or if the valve is open into the cylinder, can cause some damage if not removed. I posted earlier about using a shop vac to suck up everything around the base of the manifold before you remove it to keep this from happening

Sure did. Thanks for the torque specs too! (I don't like guessing) :D

My biggest concern is Florida sand... it's a sure way to lose a valve seat or cylinder wall.

[Been-Jammin]

A little fun in the sun! Actually there was some cloud cover, so was able to finish up early. Good thing too. It went together fairly smooth, except for an injector that ripped a seal. Sprayed fuel everywhere. Had to run out and find an O-ring... Not an easy task... Gas fumes have given me a headache and the leak cost me a couple hours.
I soaked the injectors in carb cleaner, they were really gunked up.
I added a vacuum line to the rear of the PCV for diagnosis. There was a plug there before.
I ran a can of seafoam into the new vacuum line. WOW, WHITE SMOKE for about 20 minutes. It scared me, but stopped completely after a drive.

No "Happy Dance". It is still running rough. About the same, except it's a little more pronounced under acceleration. Coils? Injectors?

The good news:
No engine codes and vacuum is up to 15 with a solid needle (no wavering or surging). Gas mileage went up to 19 from 15. Of course, I only drove ~30 miles in semi city traffic, but that's a vast improvement! The vacuum whistle is gone.

Not sure where to go from here.

[Bill R.]

seafoam in a nikasil block....






A little fun in the sun! Actually there was some cloud cover, so was able to finish up early. Good thing too. It went together fairly smooth, except for an injector that ripped a seal. Sprayed fuel everywhere. Had to run out and find an O-ring... Not an easy task... Gas fumes have given me a headache and the leak cost me a couple hours.
I soaked the injectors in carb cleaner, they were really gunked up.
I added a vacuum line to the rear of the PCV for diagnosis. There was a plug there before.
I ran a can of seafoam into the new vacuum line. WOW, WHITE SMOKE for about 20 minutes. It scared me, but stopped completely after a drive.

No "Happy Dance". It is still running rough. About the same, except it's a little more pronounced under acceleration. Coils? Injectors?

The good news:
No engine codes and vacuum is up to 15 with a solid needle (no wavering or surging). Gas mileage went up to 19 from 15. Of course, I only drove ~30 miles in semi city traffic, but that's a vast improvement! The vacuum whistle is gone.

Not sure where to go from here.

[Been-Jammin]

seafoam in a nikasil block....

I was unaware that there would be any interaction with the Nikisil. I ran a can though the intake to clean up the cylinder build up. This is the first can I've run through the intake, I used another can in the tank when I first got it in an attempt to clear up whatever was making it idle rough...

Do you know of any potentially negative effects from using seafoam in this type of engine?

BTW- I have no plans of using it again, I'm not partial to additives (however a friend is and highly recommended I try it)

[Bill R.]

your washing oil off the cylinder walls when its being sucked in through a vacum line, I won't do it on my iron block much less a nikasil block. Next fluid coming in through the vacum line like that isn't dispersed very well and it usually goes to the point of least resistance, meaning a flood of it goes to the cylinders closest to that vacum port on that back and the rest get very little... Also since you had the manifold already off you could see the buildup that was present and clean it out if any was there. Seafoam claims that there is a top cylinder lubricant present in their product but by the same token in order to clean there has to be a solvent. If you insist on using it I would only dump it in the gas tank where it can be dispersed through the fuel injectors proportionately. As for me i don't use any products of the type that are introduced either through the vacum ports or sprayed directly into the throttle body with the engine running. I've posted on this in the past and am sure i'll get the inevitable "It worked wonderfully on my car" posts.






I was unaware that there would be any interaction with the Nikisil. I ran a can though the intake to clean up the cylinder build up. This is the first can I've run through the intake, I used another can in the tank when I first got it in an attempt to clear up whatever was making it idle rough...

Do you know of any potentially negative effects from using seafoam in this type of engine?

BTW- I have no plans of using it again, I'm not partial to additives (however a friend is and highly recommended I try it)

[dacoyote]

Like I said in my first post

If you are unlucky you may have ruined a coil or two from sorting it out... or the DME, I would try coils first.... Find someone to swap with.. or get a set of ebay.. vinesauto normally is selling them... they are a little slow to ship but my set of 6 was 60 bucks with shipping. That is of course assuming that all your vac tubes are good.

-Charles

[Been-Jammin]

Just a post to say thank you to all those that took the time to share their thoughts, experiences and research. I greatly appreciate all the information, specs and tips. A special thanks to Bill R. and Lowell.

I would have certainly skipped or missed a few things without the information in this thread!

I'm going to drive her for a while and see if the problem becomes more evident over time. It is, however, definitely in better shape now and I did learn a few things along the way...

Thanks again to everyone! ;)

[Been-Jammin]

Like I said in my first post

If you are unlucky you may have ruined a coil or two from sorting it out... or the DME, I would try coils first.... Find someone to swap with.. or get a set of ebay.. vinesauto normally is selling them... they are a little slow to ship but my set of 6 was 60 bucks with shipping. That is of course assuming that all your vac tubes are good.

-Charles

All new tubing, double checked the connections and vacuum check was OK. So on to coils... hopefully after putting some decent miles on it, it will totally fail, making it obvious. In the mean time, I'll live with a little roughness. ;)

[dacoyote]

All new tubing, double checked the connections and vacuum check was OK. So on to coils... hopefully after putting some decent miles on it, it will totally fail, making it obvious. In the mean time, I'll live with a little roughness. ;)

Not to be mean... but that is a bad idea(tm)... if the car is missing.. then you are going to be working on ruining your cat....Do that and you are in for ever more money... I think everyone one the board will agree (and I the "budget" fix man)... the best way to spend more money on the bmw is to not spend money.

-Charles

[Been-Jammin]

Not to be mean... but that is a bad idea(tm)... if the car is missing.. then you are going to be working on ruining your cat....Do that and you are in for ever more money... I think everyone one the board will agree (and I the "budget" fix man)... the best way to spend more money on the bmw is to not spend money.

-Charles

Yeah, I know... *sigh*
I ordered a coil, will play swap & start some afternoon... ;)

[632 Regal]

EDIT: you did reboot the computer after all this didnt you?

You did replace the plug boots right? if so your going to have to move on down the chain of command with injectors and or coils. You can get a decent deal on injectors at:

http://www.fiveomotorsport.com/Injector_SetsBMW.asp

the new ones dont have them stupid baskets that catch crud on the tip, mine looked good at 40k, like new actually.

I didnt want to mess around doing the switcheroo with coils as I wasnt sure if that was the problem and replaced them all at the same time. Besides the coil studs seem to be a weak link here and you have to be cautious. I dont know where to get a whole set for a good price.

Good luck!

[dacoyote]

......Besides the coil studs seem to be a weak link here and you have to be cautious. I dont know where to get a whole set for a good price.

Good luck!

Vinesauto was a good deal, they worked for me...

-Charles

[Been-Jammin]

EDIT: you did reboot the computer after all this didnt you?

You did replace the plug boots right? if so your going to have to move on down the chain of command with injectors and or coils.

Sure did. Replaced the plug boots and rebooted for a fresh start.
I have a sneaking suspicion that there may be a faulty injector, they were really crudded up and some of the baskets were cracked. I'm going to have to pull it down again soon to replace the injector seals, as they were not on my list and were quite brittle. One of them cracked apart completely. I replaced it with a hardware store O-Ring which I'm sure won't last.

Thanks for the link, Bosch 0280155710 8/Set: $268.60 is much better than $80/each!

I'll continue there... Since I found a good price. May take a week or so to budget them in.

BTW- it's considerably smoother at idle now, seems to be settling down after a new tank of gas, but not yet where it should be. There's still a rhythmic miss. It seems to accelerate much better and mileage is averaging 18 city with AC on. Still no fault codes...

[632 Regal]

these dont idle all silky as you probably know but a constant partial miss is annoying, I still think I have a slight one but everything has been replaced and the miss isnt real pronounced even idling in gear with the AC on so its done. It must be the 10.5:1 and big cams right? lol
:D

[Bill R.]

stock ones flow 24.7 lbs.hour in the 530 and the five ohs are 19.7... thats over 20% less than stock....I'd try to match them with some other five oh ones instead...



Sure did. Replaced the plug boots and rebooted for a fresh start.
I have a sneaking suspicion that there may be a faulty injector, they were really crudded up and some of the baskets were cracked. I'm going to have to pull it down again soon to replace the injector seals, as they were not on my list and were quite brittle. One of them cracked apart completely. I replaced it with a hardware store O-Ring which I'm sure won't last.

Thanks for the link, Bosch 0280155710 8/Set: $268.60 is much better than $80/each!

I'll continue there... Since I found a good price. May take a week or so to budget them in.

BTW- it's considerably smoother at idle now, seems to be settling down after a new tank of gas, but not yet where it should be. There's still a rhythmic miss. It seems to accelerate much better and mileage is averaging 18 city with AC on. Still no fault codes...

[Been-Jammin]

these dont idle all silky as you probably know but a constant partial miss is annoying, I still think I have a slight one but everything has been replaced and the miss isnt real pronounced even idling in gear with the AC on so its done. It must be the 10.5:1 and big cams right? lol
:D

I just keep thinking about the 77 camaro I drove in high school... a 350 so cammed up it wouldn't idle under 850 RPM... luckily it was a manual trans... it still made a milkshake out of my prom date. She actually complained that her chest was sore from the "rocking" idle that kept her bouncing in heavy traffic.

Usually with the higher cam engines, there is a random miss and a semi random rhythm. Sweet sound. Unfortunately, the 530 has a regular skip in the rhythm, which keeps me pointed towards a cylinder miss... not a total miss, a partial miss... reminds me of a sticky valve after a hard 1/4 mile run.. ;)

[Been-Jammin]

These seem to be a better match, but I'm not that familiar with them.
Any ideas?

NEW! - 0280150947
Bosch 24lb "Blue Tops"
8/Set $299.75



stock ones flow 24.7 lbs.hour in the 530 and the five ohs are 19.7... thats over 20% less than stock....I'd try to match them with some other five oh ones instead...

[Been-Jammin]

Sorry it's been so long for a reply to this post. I just moved to Chicago and the move was intense to say the least. Selling 2 cars and a bike before moving into a high rise apartment... Oh what fun!

I drove straight through, pulling a small trailer with the race bike. I averaged about 16 MPG and 80 MPH for the trip. :D

When I arrived in Chicago, I noticed the idle was considerably smoother and have not had any issues since the trip. The car was originally purchased in Ohio, so maybe it was homesick. (he he)

Perhaps some sustained high speed use cleared out the cats?