1997 E36 M3 S52 OBD2 - VANOS and misfire codes

[e30austin]

Just did a head gasket job on a 1997 E36 M3 with S52, shark injector tune and M50 manifold conversion. We got the car all buttoned up and back together, and it runs great, but it's throwing a few codes that it didn't have before and does have a very slightly (and I mean very slight) rough idle.

I have a feeling the VANOS is out of time, but before I go tearing the whole car apart again, I figured I would come here and confirm my suspicions...

I get the following codes out of my Snap-On Ethos:

VANOS - mechanical fault - 212
Misfire Cyl 5 - 242
Misfire Cyl 6 - 243
Misfire Cyl 2 - 239
Misfire Cyl 4 - 241
Misfire Cyl 1 - 238
Misfire Cyl 3 - 240

The only thing I have to add is we installed NGK BKR6EK plugs - copper. I've had various experiences with both BKR6EQP and the BKR6EK on OBD1 and OBD2 cars, so the copper plug was my first resort. I doubt that the copper plugs would have an issue like this, but it was worth mentioning.

Any suggestions are appreciated.

Austin

[MR E30 325is]

I run the same plugs in my 98 M3/4/5 without issue. I also ran those same plugs in my S52 swapped E30, which ran like an absolute dream with them, for years. I would rule those out.

I just did a headgasket job on my M3 as well, and I am thankful I didn't have this issue when I finished it.

I don't have enough experience to give you a solid answer to this, apart from BKR6EK plugs working very well for me for about 7 years now. Anyways, did you follow a write up when you were reinstalling the vanos system? I followed the pelican parts write up myself.

Vacuum leaks can cause false misfire readings/banks running too lean codes as well. Checking for vacuum leaks is a lot easier than pulling the whole vanos system apart again.

[Jaker]

Did you connect the ground wire that goes to one of the Vanos/lifting hook bolts? I know for OBD1 it is a ground for the coils (and maybe the Vanos solenoid too).

[sweet3]

Sounds like it's out of time. Double check your procedure on how you installed the vanos. Don't suck the vanos gear in too far. The face of the unit must only just touch the head (without the gear moving in any extra). Then tighten everything.

[Northern]

Vacuum leak?

Also my cam sensor was bad and only threw a "Vanos Mechanically Jammed" Code. Easy to verify/check without pulling anything by looking at what the cam signal looks like in INPA.

[dude8383]

Double check that you didn't mess up your timing man (bottom and top) its also easy to screw up the VANOS timing as well.

We just had a mechanical jam issue with a customer car. Re-timed and the code went away.