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Old 09-11-2019, 06:33 PM
bimmer328xi bimmer328xi is offline
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Location: Washington DC
Join Date: Jul 2014
Posts: 88
Mein Auto: 2007 328xi
Great Questions. Will do some research and I have definitely looked for vaccum leaks but just can't see or find it.

1) Leaking oil from VCG
1a) I didnt see them but my impression is no.
1b) I didnt personally do that part. I have looked for leaky hoses and didnt see any. Will double check
2) I used a oil in a can smoker to smoke test it. Some smoke leaked out from the injector seals. So I replaced those and they are snug
3) Its probably around 180 after 5-10 minutes
4) This came from my friends scanner. Earlier it reported it as well. I can smell unburned gas as well
5) That's what I did to get these codes. Not sure of the rate
6) I use a Windows laptop and ODB Wiz which I have found to work really, really well.

Originally Posted by gbalthrop View Post
1) WHY did you change the VCG & WHAT (a) performance issues & (b) Fault Codes did you have BEFORE you changed the VCG?
1a) Was there any OIL in any of the spark plug wells before or after you changed the VCG?
1b) Did you change ANY of the hoses attached to the intake manifold, particularly the hose that attaches to the rear of the VC when you changed the Valve Cover Gasket?
2) HOW did you check for vacuum leak (specifics)?
3) At WHAT engine temp, or after running for how long, does the engine stall at idle?
4) HOW (what tests used) did you determine the engine "runs lean all the time"?
5) If you clear the codes and drive the vehicle, what codes return in the first 5 minutes, and what is the Freeze Frame Data for each?
6) WHAT Scan Tool or Software do you have available for reading Fault Codes, Freeze Frame Data & Parameters?

With vacuum hoses that are 12 to 13 years old, it is quite likely that removing and replacing the Valve Cover will result in a cracked hose/ fitting and a vacuum leak. Any air leak into a hose connected to the Intake Manifold admits air which is "UN-metered" by the MAF, so the MAF is telling the DME to fuel for LESS air than is actually entering the engine, hence Lean Fueling.

As for the misfire codes, if ALL THREE Bank 2 cylinders are misfiring, what those 3 coils have in common is the SAME Ground point (X6177) per this TIS Installation Location:

I would suggest providing answers to the questions above, and doing further proper diagnostics BEFORE doing anything else.

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