Reviving an old thread as I have the same issue. Ie lift the accelerator to get idle back to normal. Doesnt happen all the time. I have running a 3.5 twin plug with motec. Not mechanically minded but tried troubleshooting based on research. Cant find the idle switch .
There doesnt seem to be a secondary return spring on the bell crank in the engine bay like ive seen on other cars... i assume there isnt a spring on the bell crank on the transmission. Bushings seem fine there.
If I pull the throttle from within the engine bay, it completely pushes back. If i do the same thing from the accelerator pedal , there's it doesnt spring back to 100%
My next step is to look at the pedal cluster but i assume the pedal cluster has to come out to change out the bushings connected to the throttle pedal right? I've read that its a pain to reinstall...
Few pics for reference.
