Hoping the brains trust can help. The idle on my car keeps changing and I don't know why. Car is running great, nice and strong but lately the idle climbs 100 - 200 revs from normal when warm and then this becomes the set idle from then on.
When this happens engine idle is rough but runs smooth when driven. I then adjust idle screw back to 950 ish and it's okay for a while but then changes again. And the idle screw is not moving of it's own accord.
I have good leads, dissy cap and rotor, air filter, oxy sensor, have cleaned and checked AFM, SAD and throttle body, checked air hoses and fittings. Just wonder what to check / adjust next, any suggestions greatly appreciated .....