A4 1.6 rpm/idle changes between 800-4000

Hi Guys,

I have a '98 A4 with 1.6 injector engine.
Some days ago the engine started to run strange. The throttle valve lives its private life, I mean the idle changes from 800 to 4000 without touching anything, the throttle pedal falls in and the car starts to accelerate, the ignition becomes problematic.
I checked some contacts about the intake control valve, and cleaned too. But the problem continues. Something strange happens about the throttle control.
If someone has any idea to solve this problem by manual way (...without calling a service...) please inform me.

Thanks in advance
Wolf6494
HUNGARY

When you say that the pedal drops in the car do you mean literly?
If the pedal is acutally moving down this will mean that the accerator box has lost it's spring for some reson and requires replacment. (I prosuming that you have fly by wire) (No cable between the pedal and throttle)