e39 random stalling

[trickywoo]

My 528 has started to die randomly. Normally its when at idle but it has done it a few times at low revs in gear too. Otherwise it runs perfectly.

It feels like a misfire or extra load catching out the idle control valve before it can do its thing. It does it with the air-con on or off and lights on or off.

No electronic fault codes show up. Any ideas?

Thanks.

[DaveR]

Cam sensor?

[Fun Bus]

My E36 318Ci does this too but rarely - like 3 times in 6 months. I'd be interested to know what could be causing it.

Sorry not to answer your query but just my 2p!

[trickywoo]

DaveR said:

Cam sensor?

I thought that too but wouldn't it show up on the diagnostics?

[john_p]

Does it only happen when the engine is warming up? If so, it's a common problem on the M52TU, it's related to the VANOS seals wearing.

[trickywoo]

john_p said:

Does it only happen when the engine is warming up? If so, it's a common problem on the M52TU, it's related to the VANOS seals wearing.

Thanks, could be.

Thinking about it, it does seem to be more common 10 to 15 minutes into a drive than longer ones.

Is relacing the seals a big job?

[john_p]

10-15 mins seems a bit long for that particular problem.
My understanding is that it happens in colder temperatures, before the engine is hot, but after the 'cold start' emissions program finishes - usually about 2-3 mins after starting. Mine does it - it'll "cough" and the revs will dip down, then recover. Sometimes the "cough" actually stalls it.

The DIY to replace the seals is here
http://www.beisansystems.com/procedures/index.html

I haven't done it, but there's lots of reports on various forums with varying success. The bits aren't expensive - I don't think it's a difficult job for an experienced DIY'er, but it certainly looks time consuming !

Edited by john_p on Friday 25th June 16:26