Hey guys! help needed!
* My Audi V8 4.2 aut. -93 didn't pass emission test; CH is over 2 times too high, CO is also a bit too high. Others r fine.
* rmp goes +/- 100 when I try to keep it for example in 2000rpm. Idling is fine (or maybe there's a very little variation).
* U can feel soft rocking when u accelerate and fuel consumption display variates between 9 and 11 l/100km in 100km/h speed.
* I have changed the sparkplugs and katalysators.
When I checked the sparkplugs and they looked like engine had had 2 much gas.
* Fault diagnosis was clean.
There r no warning lights when engine is running.
Lambda signals were good i think, at least they didn't say anything was wrong when they did emission test, and they do check that.
* Could it be mass air flow sensor? could it be tested? There was no damage visible to eye, thou..
* Parts r so expensive that i want to hear if someone else has had same kind of problems, or someone knows what it could be, before i buy entire sparepart joint blindfolded..

... and sorry my english

best regards
Kari K.