Audi Repair: VW Polo, running uneven., vw polo, gasoline engine

Question
Hi.

I'm the owner of a 92 VW Polo, 1,3 litre manual transmission EFI gasoline engine. Current mileage at 63000.

Recently the engine has begun running uneven at low rpm, both when standing still, and while driving. The engine never dies. It just keeps running unevenly, and only at low rpm. The engine responds readily when I push down the gas pedal, so it's not sluggish when accelerating. Nor is it sluggish if I just make sure the rpm is above 2500.

There is one exception to this:
-The problem is not so much there just after i start the car on cold mornings, and for the first 2-3 minutes of driving, leading me to think the auto-chocke at start up prevents the problem to some extent.

I've checked the timing belt, and it seems in fine condition. I've also recently replaced the spark plugs and the rotor.

So now I wonder if you perhaps could help me with a few tips on what to look into next. Or maybe you already have a pretty good idea of what may be causing the problem?

Many thanks in advance.

Regards
Vegard Clausen
Norway

Answer
Hi there,

with out a diagnostic report it would be difficult to say the exact cause but from experiance i'd check the throttle body first, try cleaning it out, get rid of any carbon deposits,also check for leaks in either the intake, vacuum or exhaust system, especially before the O2 sensor.also try cleaning out the electrical contacts on the throttle body it self