I had some misfire for over 6months now. On cold start, check engine flashing and if i wait...EPC comes out and terrible noise and shaking when epc comes out.
Coils , spark plugs have been changed
I went to the dealer , they've done the fuel injectors and timing chain test. They are good.
They said it was the Carbone accumulation. (I feel like they just wanted me to pay an extra 660$ again) So somebody i know did a carbon cleaner job with the spray can in the combustion chamber( i think its hydrogen).
Nothing changed

And im using 94 octane fuel...nothing have changed. ..im really getting frustated putting time and money into this.
I NEED HELPP !!!!!
Audi A3 sline 2.0T 2008 143k km .

 

what are the codes?.Carbon cleaning at a indi be about $450.

 

i like your post .

 

Id be interested in the MAF readings