E34 540i - Misfrie when cold

Apr 10, 2006 2 Replies
R

Good afternoon,



I recently purchased a '96 E34 540i A/T with 170,000 km and a FSH. I drove the car from Johannesburg to Cape Town, a distance if 1,500 km ... it went extremely well, averaging 10.4 l/100km at 140km/h. However, each morning when cold the engine hunts and misfires at idle (it smells like it's running extremely rich). The revs pick up, then drop, then it misfires, then it picks up revs. Once on the road the performance is fine. The rough idle carries on for about twenty minutes until the engine is warm. I'd like to solve this problem before the engine is damaged.



Thanks for all help received.



Ralf


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likely the PCV plate on the back of the intake. Very common cold start issue, goes away when engine is warm. OR a vaccuum leak somewhere. Check the codes in the computer for a fault. join here, best e34 site ever

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E

I agree in that you have a vacuum leak. Intake manifold or the like. I'm sure you have plenty of engine codes popping up because of it. And yes, you should get it serviced, but it won't be a small job. If it's just starting thats in error, then the ignition coil needs replacing. But due to power loss and I'm sure it's making a bit of noise, you have a vacuum leak as well. It's perfectly normal for the seals to degrade. Just get your engine checked out by a bmw experienced mechanic. Good luck.

ER

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