Lost HP, Car won't go over 3000 rpms and starts jerking , What can it be please help?

[oleh]

I just replaced the fuel filter, it still does the same thing. I put the car in neutral and put the handbreak on. Reving the engine from engine compartment it still was jerking the engine the same way when it goes to 1500 rpm. When the engine is idling there is no jerking it runs smooth.
-Could it be spark plug wires?

-I checked my engine codes, the code goes 1233 which means Throttle Wide Open Throttle Switch. Could that be the problem? If yes were is it located? Do i have to get a new one or can it be fixed?

Someone plz help me!!

Yes its an M30 Engine 3.5L

[Jeff N.]

Check for a loose crank position sensor. Search the archives, should be instructions. Or on BMWe34.net...

[Blitzkrieg Bob]

Could be a couple of simple things like, fuel filter and tune up or

could be something more funky like the MAF/AFM

[oleh]

Could be a couple of simple things like, fuel filter and tune up or

could be something more funky like the MAF


I dont know i just bought this car awhile ago all i replaced is spark plugs.

Whats MAF?

[632 Regal]

yep, check the CPS first, then replace the fuel filters (note the correct direction of installation) and then go from there.

Could be a couple of simple things like, fuel filter and tune up or

could be something more funky like the MAF

[oleh]

Were is a crank position sensor located?

[oleh]

What is CPS and were is a fuel filter located sorry i dont know alot about beemers.

[632 Regal]

AH HAH! WHat plus did you use???

[oleh]

i checked my engine codes, the code goes 1233 which means Throttle Wide Open Throttle Switch. Could that be the problem? If yes were is it located? And what do i have to do to fix it?
Im using NGK G Power Platinum Spark Plugs.

[Blitzkrieg Bob]

is it smooth?]

[Blitzkrieg Bob]

on the front of the block, mounted to read the notches on the harmonic balancer.

English translation= look for the big pulley on the front of the motor, see the one with all the teeth? look for a electrical thingy aiming at the teeth. check to make sure it's pluged in and mounted well.

Fuel filter is under the back, behing the rear end on the passenger's side. Looks like a can with a hose coming out of each end.

Good luck

[oleh]

is it smooth?]

its not smooth like a new car its shaky little bit.

[632 Regal]

HELLO what plugs did you use???

[oleh]

i checked my engine codes, the code goes 1233 which means Throttle Wide Open Throttle Switch. Could that be the problem? If yes were is it located? And what do i have to do to fix it?
Im using NGK G Power Platinum Spark Plugs.

[oleh]

HELLO what plugs did you use???

Im using NGK G Power Platinum Spark Plugs.

[Blitzkrieg Bob]

opposite the linkage. black plactic box with a three pin plug.

Check the plug to make sure it's hooked up and contacts are clean

[Alexlind123]

its not smooth like a new car its shaky little bit.

Sounds like an M30, at least mine.

[athflying79]

Im using NGK G Power Platinum Spark Plugs.


You'll want to remove those and put some Bosch W8LCR's in. That will help the idle. I would spend some time searching this site and BMWE34.net for some all around good info for your car. You'll also want a Bentley manual.

[oleh]

I just replaced the fuel filter, it still does the same thing. I put the car in neutral and put the handbreak on. Reving the engine from engine compartment it still was jerking the engine the same way when it goes to 1500 rpm. When the engine is idling there is no jerking it runs smooth.
-Could it be spark plug wires?

-I checked my engine codes, the code goes 1233 which means Throttle Wide Open Throttle Switch. Could that be the problem? If yes were is it located? Do i have to get a new one or can it be fixed?

Someone plz help me!!:(

Yes its an M30 Engine 3.5L

[genphreak]

Sounds like an M30, at least mine.If the plugs have the right gap, NGK/Bosch whatever- they shouldn't just stop working at 3000rpm. Check fuel pressure and that the Air Flow Meter flap is not bogging when part-open. On some cars the AFM's body warps (heat/age) - perhaps it happens if the becomes overheated (I dunno). IN this case the flap inside that senses the flowrate of air passing into the engine actually sticks. You can sometimes see scrape marks if it has been happening for a while. (If you take the rubber boot off it on the air cleaner side. Check my previous posts and be careful about how you reseat the boot- none of them must leak and they mustn't be too tight either. If the sealing faces show signs of leaking (ie dirt ingress or roughness) or you have a hole or a split in your the boots/air intake pipes anywhere, that HAS to be attended to before the car will run right.

Don't forget to check your Idle Control Valve and Throttle Position Switch are both operating on spec as others have suggested if idle is really poor. :) Nick

There is no adjustment other than a idle-air-bypass/CO adjuster screw- and this is unimportant until everything else is confirmed 100%.

[Alexlind123]

If the plugs have the right gap, NGK/Bosch whatever- they shouldn't just stop working at 3000rpm. Check fuel pressure and that the Air Flow Meter flap is not bogging when part-open. On some cars the AFM's body warps (heat/age) - perhaps it happens if the becomes overheated (I dunno). IN this case the flap inside that senses the flowrate of air passing into the engine actually sticks. You can sometimes see scrape marks if it has been happening for a while. (If you take the rubber boot off it on the air cleaner side. Check my previous posts and be careful about how you reseat the boot- none of them must leak and they mustn't be too tight either. If the sealing faces show signs of leaking (ie dirt ingress or roughness) or you have a hole or a split in your the boots/air intake pipes anywhere, that HAS to be attended to before the car will run right.

Don't forget to check your Idle Control Valve and Throttle Position Switch are both operating on spec as others have suggested if idle is really poor. :) Nick

There is no adjustment other than a idle-air-bypass/CO adjuster screw- and this is unimportant until everything else is confirmed 100%.

I was talking about the slightly rough idle-actually mine has been better of late, i dont know why.

[genphreak]

I was talking about the slightly rough idle-actually mine has been better of late, i dont know why.Oh sorry, read it wrong there, my bad. I heard good things about the new NGKs though (we are talking about the new micro-electrode ones no?). The old Boschies are certainyl tried and true. I have run the same set of Bosch platinums since my head rebuild (and they still go fine, but many report fouling with these- I suspect it might occur more easily in worn engines) I will pull mine and post some pics shortly, they've done 20,000 or so now.

[Jeff N.]

Do you have an automatic or manual? The WOT switch is different on each. I'm familar with the manual version only. It basically is a 3 position switch. Position one is idle, position 2 is mid throttle and position 3 is WOT.

It's not impossible that you switch is stuck on the idle position. Bentley's has simple instructions on how to adjust it and you should follow those. If you have a manual, a quick test is this:

- engine off
- in the engine bay, pull the thottle cable so that it 'accelerates' the car
- listen carefully to the little black box on the opposite side of the throttle plate
- when you just open the throttle, you should hear a distinct "click" sound in the box.
- release the throttle plate, and you should hear another click

This is the micro switch for idle circuit going on / off. You won't hear a click for the WOT setting. The switch can be adjusted via the two mounting screws or sometimes they get old and gummy. Not a fixable part really, you need to replace it with a new one.

Here's a pic of a TPS switch from a manual engine to help you visualize what's going on.

http://home.comcast.net/~jsnord/pics/tps.jpg



i checked my engine codes, the code goes 1233 which means Throttle Wide Open Throttle Switch. Could that be the problem? If yes were is it located? And what do i have to do to fix it?
Im using NGK G Power Platinum Spark Plugs.

[Rustam]

its not smooth like a new car its shaky little bit.

biggest advice - get-your-self-a-ben-tley-ma-nu-al...