I'm just looking to pick brains.... for info (not for food like a zombie)

My car: '97 A-6 Quattro 2.8L auto AFC engine w/170k miles.

Over the last year or so, I have gotten random CELs, that the VAG-COM says are: 16554.P0160 fuel trim, bank 1: malfunction
16557.P0173 fuel trim, bank 2: malfunction

It will clear and not come back for months, but after the 2nd event, I went ahead and changed the O2 sensors on the manifold. That was 8 months, and 3k miles ago, and I have had the same CEL (with the same codes ) repeat a couple more times since then.

Any ideas of something intermittent and common to both sides of the engine? Maybe a vacuum leak... ugh.. I should poke around and move hoses to try and make the CEL light come on?

thanks for the help!

 

Vac leak is possible. I would try cleaning the MAF too and see if that helps.

 

Thanks, I'll try the MAF.