E90 engine light vanos valve

[fraz1001]

My old man has a 2011 E90 318i m sport

The engine light came on the other week so I plugged it into my diag tool and got 2A99, which relates to exhaust vanos solenoid.

After doing some research online it appeared the solenoids are prone to sticking

The car has done 39k with FBMWSH.

The light was only coming on after a cold start and if I switched engine off and back on it would clear.

I removed the valve and cleaned with brake cleaner,that worked for 5 days and then the light reappeared.

Next job I did was swap the inlet and exhaust solenoids,did an engine flush and oil and filter change,that was 2 weeks ago and the light hasn't returned.....

I'm guessing swapping the valves over makes them work at a different point in there range hence it is not sticking any longer?

[nomis36]

I had a similar issue when I had my E36 M3 which was confusing given I had a recent receipt for full vanos rebuild just before I bought the car
I removed the solenoids and found one of the O rings perished to hell and obviously letting pressure past. After replacing all the O rings never had another problem so I'd have recommended for the negligible cost replacing them while you had the solenoids out. Next time eh?

[fraz1001]

nomis36 said:

I had a similar issue when I had my E36 M3 which was confusing given I had a recent receipt for full vanos rebuild just before I bought the car
I removed the solenoids and found one of the O rings perished to hell and obviously letting pressure past. After replacing all the O rings never had another problem so I'd have recommended for the negligible cost replacing them while you had the solenoids out. Next time eh?

Thanks for that, the seals looked perfect but I shall bear that in mind if I encounter any more trouble with them.