I've been finding recently that my 1.6 AEE mpi Felicia is doing strange things. Sometimes the revs stick at 2000 revs for 2-3 seconds after I release the throttle. I'm also finding that it's impossible to rev the engine to between idle speed and 2000rpm. It's either idle speed or 2000 rpm. Also sometimes when I start the engine, even when warm, the revs go all over the place; they'll start very low then creep up over the following 5 seconds and then stick at 2000rpm again. When this happens, I also get a louder than normal exhaust sound - sort of metallic sounding. The problem is intermittent - I switch the engine off then on again and it goes back to normal some of the time of the time, though sometimes it takes several engine restarts. Very weird. I tried cleaning the throttle butterfly valve as it was quite oily, but it's made no difference. The throttle cable doesn't stick, and the butterfly throttle valve moves freely. I'm wondering if its an ECU problem, or perhaps I've got a bad throttle position sensor, or some other sensor. Any ideas?

Edited 8 January, 201016 yr by paulknightmalci

you could try resetting the throttle body adaption using vag-com, but there is a known fault on some ecu's that cause this too

you could try resetting the throttle body adaption using vag-com, but there is a known fault on some ecu's that cause this too

Took it to the garage. They just resetted the ECU and cleaned the throttle body and it seems fine - for now. Thanks for your suggestion anyway.

the other thing that the vdo throttle bodies are really well known for is the idle switch busting in them which causes the revs to constantly rise and fall around 1500rpm