1.9 Running Too Lean

[Tjalde^ 1]

Hello,

 

My 1.9 is running a bit too lean. I am not really sure, what the analysis of the exhaust gas said in details, but the mechanic said it ran a bit too lean.

I have tried to adjust it with the screw on the AFM, but it turns out, it does change on the mixture.

 

Is there any way to make it run a but richer?

 

Kindly regards,

Jens-Jakob

[DamirGTI 342]

The allen screw on a AFM is for idle mixture only . For real fuel trim (for all the rev range) you'll need to "play" with the AFM flap spring tension .

 

I'd first double check driving on board with an wideband lambda sensor hooked up , to see if it goes increasingly lean at some spot of the rev range and tweak the AFM spring tension if needed .

If it's just the idle mixture which is a bit lean , can be rectified by turning/adjusting the said allen screw .

 

One more thing , need to check that you do not have any vacuum leaks , cos this will create lean issues and might "mask the problem" .

 

D

[Tjalde^ 1]

Thank you so much for the detailed answer. I will try to get my wideband lambda mounted. Then I will find out how big the problem is.