N46: Timing issues after replacing valve stem seals and timing chain?

[XBTC]

Hi all,

my E91 (N46B20 motor) was using +1l of oil per 300 miles. So I had valve stem seams replaced and the timing chain (just as a preventive measure there was nothing wrong with it).

Now the motor is not consuming oil anymore which is great. However I have the feeling that it sounds more gnarly above 2000RPM than before (a bit more like a Diesel engine) and feels slightly less powerful than before. In idle the engine runs perfectly smooth.

So my question is: Could it be that they somehow slightly messed up the timing of the motor or is it just my imagination? Is it possible when replacing the timing chain to skip a cog on the wheels of the vanos units? Or would this result in a much more drastic misbehaviour of the motor?

Is there a way to check the timing / vanos unit using diagnostic software (I have INPA, EDIABAS, etc. but currently no faults are reported)? Or is this only possible via dissasembling and manually checking the timing with the camshaft locking tools?

Many Thanks in advance!

[Codes2]

Hopefully someone will chime in with regards to using software to verify timing/vanos.

I've read a few postings where the teeth jumped one, and the car ran, but rough.

I'd take it straight back to the garage (under 2k rpm) and have them guarantee it's correct.

[XBTC]

Hopefully someone will chime in with regards to using software to verify timing/vanos.

Yes that would be greally great to know, as I cannot easily take the car back to the workshop (it is 400 miles away from where I live).

When I check with INPA there are no fault codes and no other issues, except for the camshaft adaption values that are slightly out of range:





Does this have any relevance? Should I reset adaption values via INPA?

[XBTC]

Is there some kind of official manual by BMW that describes the INPA values in general and what they mean and in which range they should be?

[Codes2]

Is there some kind of official manual by BMW that describes the INPA values in general and what they mean and in which range they should be?

Sorry bro.

RocketSurgeon and a few others would be the best bet.
If they're not chiming in (busy, etc), then you should be posting to other forums too.

https://www.n54tech.com/forums/
https://www.bimmerpost.com/