Hi all,

I've got a 1999 Audi A3 1.8i Sport that belongs to my father-in-law; I'm doing it up ready to sell. I'm a fairly novice mechanic and I can manage to change filters, plugs and I've already done the starter motor.

The problem I have is that the car is not performing anywhere near a 1.8 injection petrol. It feels more like a 1.1.

The main problem is that under acceleration, the engine power is very jerky with flat spots all over the place (but not at predictable RPM). It struggles to get to 90mph.

Another symptom that may be related is that if I stick the car in neutral and coast, it will sometimes cut out. I can see the RPM is stable at ~800RPM, then it will start to dip down to 500RPM and sometimes cut, sometimes not.

The only other symptom I can think of is that it seems fine when running on choke (although I'm reluctant to drive it hard when cold to fully test it).

Does anyone have any ideas where to look first? Any known faults? I'm thinking air sensor, exchaust sensor, or fuel pump, but they're nothing more than (pretty uneducated) guesses.

I've just replaced the mid and back silencers because of a slight blow, but that didn't help.

Any help gratefully received!

Cheers,

Loz

 

Just for future reference, the problem was a faulty MAF sensor.

Replaced it, disconnected the battery for 20 mins, reconnected, all ok now.