Erratic engine behavior

[Boone.Msi]

I purchased a 1995 BMW 530ia with 99000miles at a prive import dealer. The car started, idled and drove exceptional. With that in mind and two test drives i wasnt worried about the Nikasil problem.
Anyways, 2 months later and my idle is completely f*d. Ive searched and read over a hundred threads on this forum and there seems to be so many different things that can cause a rough idle, i cleaned out the MAF, got new bosch spark plugs and tomorrow im gonna clean the idle control valve. Other than that i dont want to spend alot of money doing a checklist repair. Here is exactly what happens everyday now.

I start my car around 6am every morning, it sounds like its barely alive, sometimes stalling until i give it gas keeping it at 1000 rpm. it'l make a chugging noise for the first 3-5 miles traveled durring idle. after i drive it a little it acts completely normal until i stop for more than a minute. Then the rpms will drop randomly to around 400rpm and stay like that until it stalls or until i drive again(whichever comes first)

I noticed out of anger when i accelerate hard in sport mode the problem magicly goes away and the check engine light/rpm drop happens less than half the time if i kept it in economy mode. im tired of having it stall while im stopped on a busy highway and i need to fix this asap. Unless you guys know what this is; here are the steps im going to go through with

1. clean ICV
2. New 02 sensors
3. Check all sensors that may be possible culprit
4. Check All vacum lines as best as i can
5. New fuel pump
6. New valve cover gaskets
7. chip it(heard it helped some people)

there is one other thing. i have leaky valve cover gaskets that has let a small amount of oil around the spark plug coils. Maybe my coils are shorting out? what would be the effect of a shorted out coil.(noise of the engine, rpms, etc?)

thank you to everyone that helps, i love this car and i really want to keep it alive.

[stu1]

I think I'd be inclined to make sure the mechanicals are good first with a compression test and mebbs a leak-down test. If that's Ok, then things aren't too bad :)

[brosher]

Read through this entire thread:
http://www.bimmer.info/forum/showthread.php?t=15686

and here:
http://www.bimmer.info/forum/showthread.php?t=17421

My M60 is doing the same thing, guess it is pretty common this time of year. I ordered all my gaskets and they'll be going in next weekend.

[Boone.Msi]

damn... looks like im gonna be busy next weekend. Figure il do the pcv plate, intake gaskets and valve cover gaskets all in one weekend.

thanks for pullin that up for me. guess it was the only one i didnt read...

Im gonna see what happens when i clean the ICV and put in the o2 sensors tomorrow. If saturday morning its the same it looks like im gonna have to fork out the money ive been saving for the M parallel staggered set... Damn it...

[Boone.Msi]

well there was a ton of crap in the icv. i almost clicked my heels when i saw it. only to be thrown back to my checklist. Cleaning the ICV didnt help the idle... Only seemed to help it from stalling, since i didnt stall today. Looks like o2 sensors tomorrow.

[Boone.Msi]

well i got new o2 sensors, not one bit of change. Im gonna tackle the new intake manifold gaskets and valve cover gaskets begining of next week. Do you guys think that leaky valve cover gaskets could be the only reason for this? i dont want to spend two days on this and it still act the same.

by the way, anyone got any pics of their painted valve covers? im thinkin about painting mine silver while theyre off.

[BillionPa]

check to see if the coils are at the right ohmage, and pull the spark plugs and check their condition. a rapidly deteriorating condition like yours is usually do to bad fuel, what kind are you putting in your car?

get a fillup from 1/8th tank with 92-93 octane ETHANOL FREE gas, drive for about 20 mins, then open the e-box and yank the ECU harness plug off and the trans computer harness off.

then let the car sit like that for a day while you charge the battery using a trickle charger such as the bmw one.

my car runs like total crap if there is any ethanol in the gas or if the batt voltage is a bit low.

also check to see if there is oil in your coolant...
there is also the crank ventilation thing at the back of the engine that can make the car run EXACTLY like you are describing, but do the gas thing first to narrow it down.

i have one sitting in my garage waiting to go into my car when mine starts running bad. its about $70 for the kit at bavauto.com

[BillionPa]

oh and i am painting my valve covers too :D

i just dont have much time, so it will probably be a year before its done :/

[Boone.Msi]

il try that tomorrow. although ive put nothing but 93 octane in the car since i got it. ive been fillin it up with quicktrip gas and flash foods(american) gas. and i thought it sounded like a fuel problem too. so now im just gonna fill on exxon and BP. i swear its gotta be a sensor problem because it will drive perfect and then i stop it makes a "click" noise and it stall or idles like its on its dying minute.

i know i have a valve cover leak so whatever might as well fix that too.

it just seem like things are getting worse. since im sick of listening too it idle like death when i first start it i just give it some gas, back out and head down the road. problem is that its idling so bad that my power brakes/power steering dosent want to work so well = accident, untill it warms up.

[BillionPa]

click or pop?

if its popping its usually vacuum pulling oil through the plug threads with air.

clicking may be a coil shorting.

[Boone.Msi]

and ive replaced the intake manifold gaskets, pcv plate, all deteriorated vacum hosing, valve cover gaskets, o2 sensors, switched to ngk sparkplugs(bosch paltinum 2's were black from running rich)

it idles smooth but when i stop at a light the rpm's will drop slowly until it stalls. also when starting, it sounds rough like its misfiring. my friend swears that its a shorted coil. he swapped them from drivers side to passenger side and says he can hear a difference from each side. I cant tell a diference and i have one hell of an ear.

i can either gamble on this problem some more or have a diagnosis for $75. will the diagnosis be able to tell if its a bad sensor and/or a bad coil. My last gamble would be the crank position sensor($75).

what should i do? buy the sensor or have it diagnosed first?

[632 Regal]

tough call, the stealer will replace until they hit the problem. might br easier economicly to replace the item. whats the stomp test tellin you? Have codes read by one of them peak code readers?

good luck bro, been following this thread and figured you had it fixed by now.

[bbig119]

Boon,

Did you get this sorted out? I'm having problems with my car not starting well and stalling out if I slow down/idle.

My symptoms are similar to yours except that many times the car is unresponsive to throttle, will stall when I add throttle, or rpms will start going up only to stop and dive down stalling more often than not.

The idle surges from 300-above 1000 rpm. Usually I'm only able to get the rpms up above 2000 when I give it gas during one of these idle surges, otherwise it'll stall.

When I'm able to get the car moving, it tends to be jerky. However when I get above 3000 rpm is tend to be stable, but as soon as I slow down or stop, then I'm back to the idle problems/stalling, etc.

So from what I've read it appears that my checklist is similar to yours, but I'd like to know if you ever got this hammered out.

Thanks,

Bryan

Edit: Should point out that its throwing code 1221.

[BillionPa]

i seem to recall this problem also being caused by the AC compressor. since its winter, cut the belt. actually the root of the problem is the AC control unit (yes this is my horrible experience) turning on the compressor clutch whenever it felt like it.

i doubt its the crank sensor, as the symptoms would be... worse.

[bbig119]

i seem to recall this problem also being caused by the AC compressor. since its winter, cut the belt. actually the root of the problem is the AC control unit (yes this is my horrible experience) turning on the compressor clutch whenever it felt like it.

i doubt its the crank sensor, as the symptoms would be... worse.

Would I be able to see this/confirm this without cutting the belt?

[Fetch]

I do not recommend cutting the a/c belt at all.
Because it is winter, you should especially make sure to cycle the a/c once per week at least, to keep the fluid lubricating the motor. Also, with a/c on you can better defrost your windshield.

[BillionPa]

yeah, you can just remove it, although i think you have to remove the main belt as well.

while they are off you can check for tension in the water and power steering pumps.

drive it for a day or 2, and if you have no issues, you narrowed (enough) it down to the compressor clutch.