Yellow warning: Fuel trim banks & Misfire, cylinder 5 6 4

[jbrodin]

Hi

I get a yellow warning light every now and then. There are quite a few messages in the reader. I suspect they are all related since they all started to show at the same time shortly after being at a garage to replace the ABS module. Hopefully one of you have experience of this and can advise how to sort it out.
CB Fuel trim bank 2 control limit
F2 Misfire, cylinder 5
F3 Misfire, cylinder 6
F1 Misfire, cylinder 4
E4 Fuel trim bank 2, permissible range exceeded
BF Insufficient heat output, oxygen sensor behind catalytic converter, bank 2
E3 Fuel trim bank 1, permissible range exceeded

Thanks,
Jonas

 

[NZ00Z3]

You likely have a vacuum leak. Check the rubber tube from the MAF to the throttle body for cracks etc

 

[jbrodin]

Hi, have finally got around to replace both upper and lower rubber tube from the MAF. Disappointingly, the yellow warning light keeps coming back.

08 Signal, air-mass flow sensor
E3 Fuel trim bank 1, permissible range exceeded
E4 Fuel trim bank 2, permissible range exceeded
CB Fuel trim bank 2 control limit

What’s next, do I need to replace the MAF sensor?

Thanks

 

[AntStark]

Smoke test to confirm no more leaks first

 

[jbrodin]

Bought a smoke machine. Found a leak and replaced the valve cover gasket. No visible leaks after that.
Yellow warning light coming back on after more than an hour with the following codes:
08 Signal, air-mass flow sensor
E3 Fuel trim bank 1, permissible range exceeded
E4 Fuel trim bank 2, permissible range exceeded
BF insufficient heat output, oxygen sensor behind catalytic converter , bank 2.

What’s next? Should I bite the bullet and buy a new MAF sensor?

 

[Neilb62]

Could you unplug the MAF and see what happens? It will run iirc?