Quantcast
Channel: Auto-Professionals - All Forums
Viewing all articles
Browse latest Browse all 7476

BMW E46 M3 2002 Randomly Stalls No DTC's

$
0
0
Car is 2002 E46 M3 WBSBR92090EH76593

I was asked to look at car as it randomly cuts out and has difficulty starting afterwards.

First attempt I found fault codes for exhaust side of VANOS, and I could see live data for VANOS was moving all over the place.

So car went to a friend's workshop and had another (used) VANOS fitted, and full service. Before replacement VANOS car felt like maybe a 320i when driving, after VANOS, M Power has come back.

However problem did not disappear however now we get no fault codes so we carried on a little further and removed idle control valve, cleaned with brake cleaner and refitted. After cleaning the valve, we noticed the valve would rattle if you shake it, but I spoke to a friend of mine who told me this was normal for this valve on these cars.

Both lambdas switching at pretty much exact same time and almost identical values so I doubt it's a lambda fault.

Smoke test performed and no leaks found.

What we find is the idle isn't perfect (occasionally drops maybe 50-100rpm), and sometimes it can be left idling all day, sometimes it may cut out after just a few mins.

If it gets fully warmed up it doesn't cut out any more, only cuts out when cold/warming up. If we disconnect MAF then idle is perfectly stable.

However I have sat watching MAF values when it stalls and nothing unusual there, just when it stalls Kg/h just quickly drops to 0 immediately after engine stalls.

If anyone has any ideas I would be very grateful as this is driving us crazy.

Viewing all articles
Browse latest Browse all 7476

Trending Articles



<script src="https://jsc.adskeeper.com/r/s/rssing.com.1596347.js" async> </script>