E36 328 cutting out at low revs

[james328i]

Over the last 2 days my car has developed a problem. When the revs are dropping and car is coming to a stop the engine cuts out. There is also a lumby idle. Not very bad but noticeable.

Any ideas?

Cheers

[Shropshiremike]

james328i said:

Over the last 2 days my car has developed a problem. When the revs are dropping and car is coming to a stop the engine cuts out. There is also a lumby idle. Not very bad but noticeable.

Any ideas?

Cheers

Get the diagnostic port read - wouldn't be surprised if it's a cam/crank sensor. Could also be ICV as well ...and check the rubber intake boot for cracks/splits...especially if it's the original one

Edited by Shropshiremike on Thursday 2nd September 14:45

[james328i]

Checked the hose for splits earlier and all seems ok. What I did notice a few days ago was that the throttle seemed to stick on now and again for a second or two. I checked the throttle body earlier and it seems to be pretty clean. It could just be co-incidence. T

he car is just about driveable so want to get this sorted before the problem gets worse. When the car is driving it's fine. Problem only occurs when coming to a stop/breaking or on idle.

[V8mate]

Does it fully cut out and stall, or just dip down to 'battery light on' level and then surge?

[dan101smith]

I'll put a fiver on this being the cam/crank sensor. All the usual signs.

[james328i]

Thanks for all the replies. Managed to get a good look at it last night. Turns out to be some sort of air leak underneath the inlet manifold. When revving the car I can hear air escaping from underneath the inlet. I didn't have a chance to remove it last night so will have a go on the weekend. Are there any known pipes to split underneath the inlet?

[V8mate]

There's a little (1"?) pipe which runs from underneath the inlet manifold and connects to the underside of main tb boot. These often split at the union between the two. I had the same problem recently - replaced the tb boot, the union itself and the 'J' hose, plus all jubilee clips for £23 with parts from main dealer.

[james328i]

V8mate said:

There's a little (1"?) pipe which runs from underneath the inlet manifold and connects to the underside of main tb boot. These often split at the union between the two. I had the same problem recently - replaced the tb boot, the union itself and the 'J' hose, plus all jubilee clips for £23 with parts from main dealer.

Is it possible to replace without taking off the inlet? I hope it's this. Was it a PITA to change?

[V8mate]

james328i said:

V8mate said:

There's a little (1"?) pipe which runs from underneath the inlet manifold and connects to the underside of main tb boot. These often split at the union between the two. I had the same problem recently - replaced the tb boot, the union itself and the 'J' hose, plus all jubilee clips for £23 with parts from main dealer.

Is it possible to replace without taking off the inlet? I hope it's this. Was it a PITA to change?

Just the 'J' hose? Sure, it's a bit fiddly getting round to where it connects to the 'engine'. The whole job must have taken me at least... 3 minutes... though. Not sure why you found the tb boot an issue.

In my case, the part of the tb boot AND the 'J' hose had both perished around the nylon union.

The 'J' hose is part 10 below., but the tb boot has a bit of 1" pipe sticking down below it, ahead of the union, which you can't see in the diagram.

[james328i]

I was just looking for that diagram on Real OEM. Cheers. I don't think it's a problem with part 10. The noise is actually coming from underneath the inlet manifold somewhere. But on the diagram is doesn't show any pipes in the area the leak is coming from if you get me? I think the J hose is ok without any wear.

[NiceCupOfTea]

Classic symptoms of a vacuum leak.

[CPCauto]

Sounds like the crankcase pressure valve has a split diaphragm. With the engine idling, unscrew the oil filler cap on the rocker cover. If it feels like it is being sucked down onto the rocker cover , then this will be your problem. About £35.00 for the part from the dealer, can be fitted without removing the manifold but is fiddly. Also worth a look is the plastic corrugated hose from the rocker cover to the crankcase valve. In any case , you will probably snap or crack the hose when it is removed anyway.

[alan36]

Hey guys are these parts the same for a 323i. If so I have the same problem but I dont know what you are talking about and where to look. I have checked the "j" pipe and thats ok but I dont know where any of the other things you mention are.

And there is an air leak sort of noise coming from the rear area of the engine and when I turn the engine off it sort of makes a ppppsssshhhtt noise.

Help please

Alan

Edited by alan36 on Saturday 4th September 13:32