Idle fluctuates between 1000 and 300 RPM. Stalls at lights or going slow when cold, slightly better when warm

[pinki]

This started yesterday and the car is practically undriveable. Car had been working as well as a 1997 1.8 Audi A4 can.
The car starts easily, but without the accelerator being pressed down will stall in seconds - very unusual for this car.
Going at a snails pace or stopped the car stalls. When warmed up it will stall less but RPM needle may dip to 300 before bouncing up again.
Also the car squeals for 1 second when started. This only started yesterday or the day before. Would it be connected?
I have bought injector cleaner and added to the petrol already, though I do not think it is a fuel issue as ok at 50MPH.
I got throttle cleaner, i will look into doing this tonight or tomorrow, forums seem to suggest this can gum up and clog a bit.
Can people please advise on what else to try or check?
The garage would not be able take the car till next week but I need to drive it over the weekend so all help greatfully received. Thanks.

Engine type is ADR if that helps.

[warptechno]

I had the same problem few years back. I've got the ADR engine aswell with an auto box and when pulled up to lights it would rev between 1000 to 300 but gradually got worse almost cutting out. I got a local garage to repair and problem was throttle body required cleaning. If you are going to attempt investigation and removal of the throttle body - I believe it requires Vagcom to reset it on refit.

Good luck.

[pinki]

Cheers for the warning warptechno.
I had wondered about removing the throttle body and sensors.
A friend has told me when he used the stuff, he had the air filter off, the car reving, and sprayed the stuff up the intake and that did the job, so if I hear no screams of "You must be joking/Mad" that is what I will try in the first instance.
Also putting me off removing the throttle body is my local spares shop don't do gaskets for it, though they did suggest doing my own flexible gasket.

[Crasher]

After cleaning the throttle body should be re-matched to the ECU using a diagnostic computer. You will not be able to clean it adequately unless it is removed,

[pinki]

I sprayed a fair bit of TB cleaner up the air intake after lifting it off the filter. I did this on Fri before a bit of a drive but it did not help particularly.
OK I was too chicken to remove the throttle body housing after reading the above, but tried to have a go at a bit of cleaning.
I removed the air intake to the TB, there was oily gunk on the bottom of the tube, but this may have been as a result of my spraying.
I cleaned this out and wiped around the butterfly valve, and the inside by pulling the throttle spring. Inside there was some deposit on edge of valve and on side walls. Cleaning this did not resolve the issue but seemed to reduce the problem - quicker to stabilise from cold.
I removed the MAF and a visual inspection showed revealed nothing unusual (to the novice). There was no visible breaks in the sensor wires and i cleaned the contacts a bit.
The car is booked into the garage tomorrow morning as it needs fixed, and I will update the thread with the garage findings so it may be of use to others in the future.
I will have some free time later if there are any more suggestions.

[pinki]

The car is in the Garage, and I had a thought...
I had been trying to replace faulty bulbs in the instrument cluster, and disconnected cables temporarily for easier access. Would this have had any effect?

[warptechno]

Wouldn't have any effect unfortunately. You could, theoretically, run the car without any of the instrument panel connected (not advisable!)

[pinki]

Got the car back and running smooth again. The garage cleaned the throttle body housing and reset to eu. It cost £49, but well worth the change in performance.Unlikely to be done again in cars lifetime, but may consider having a crack at it myself next time.
Thanks to warptechno and crasher for their contributions.