[omadab]

Hello, I have a 2011 328xi e92 6MT with 135 000 km.
Check engine light came on 2 days ago for 2A98. Took it to bmw and they diagnosed vanos solenoids (using puma m?). Replaced both solenoids for a nice 600$. Cleared all error codes using INPA. Started car up, instantly on startup still the same code. I swapped both camshaft sensors with each other. Now, i have code 2A98 AND 2a99. Going back on Monday to ask for my money back, but realistically probably gonna get nothing.

Work done on engine:
Spark plugs, Ignition coils, air filters --> 110 000km
Engine was retimed a while back because of me being dumb but ran for almost 10 000 km with no idle issues.
Opened up the valve cover again here \/ to check for timing... looked good.
VCG and eccentric shaft sensor ----> 132 000km

Recently: BMW got me to change over to 0w30 for some reason so I did it. Car ran fine for a couple hundred km.
Non return valves were cleaned recently with brake cleaner
I also noticed that inside of my oil filter cap, the mesh looks smaller than the ones in everyone elses car. Does the post-lci have a different oil filter cap/mesh filter (for the vanos)?
I'm praying right now that it is not the camshaft ledge seals but at this point everything is pointing towards that ...

Edit: Forgot to add on startup instantly the idle will go up to 2k rpm then back down to 500rpm, bring itself back up to 1.5k and then go back down to 500/600 happens almost every time the car is started.

[e91Owner]

Yes, you've pretty much covered it. If you have already replaced the solenoids, it is likely the camshaft seals. If you already have a cable for INPA, you can download ISTA for about $10. It will have the full diagnostic procedure for those faults.

[omadab]

An Update

Before the car suffered of 2A98 only. I swapped the camshaft sensors to see if that was the issue but then 2A98 and 2A99 showed up. Went to the junk yard and got 2 camshaft sensors and 2 mafs. I replaced the exhaust camshaft sensor and now the code is no longer current, (only pending or permanent). I replaced the intake camshaft sensor and there is no change. I replaced the MAF and the rough idle fixed itself pretty good. As mentioned before both vanos are brand new from bmw dealer. The car runs and drives decent right now so for now I'll keep driving it and tomorrow I'll bring it to dealer and see what happens.

[omadab]

Another Update

Went to BMW to complain because of the vanos solenoids. Not surprised... they're giving us nothing. Spent about an hour speaking with one of their best techs. We have come down to the conclusion that the timing must have slipped. In the next couple days we will be retiming the engine. However I wanted to know if anyone knows of a way to check for timing chain stretch without having to take it out of the engine. Thanks in advance

[omadab]

Retimed the engine and the codes no longer popup on inpa. However now there is a misfire in cylinder 1. Swapped the coils and code did not follow. Swapped the plug and it did follow. So now I've ordered 6 new spark plugs. Hopefully this is the end to my engine issues

[Suvorovo]

Did your 2a98 code come up during cold oil temperature and at what RPM? Having same code come up rarely and it's always when the oil temperature is 9C, 11C,19C.