high idle while driving

[Jarek5_7]

I got the MArk Heibeck chip today and I have installed it. works great. mainly I wanted it to get rid of the high idle issue after stop etc. and hot restart etc. its gone now. idle drops down right after stop and after hot start engine idles low like never before, so its great. my z is 1990.

I have one issue left only, when driving and letting off the accelerator rpms wont go below around 1250 so sometimes when driving slow and in gear I have to use brakes to slow the car even if accelerator pedal is let off but engine forces the car to go faster to stand with the 1250 rpm while in gear. and when putting clutch on and slowing down the car, rpms are higher than they should be but after stopping the car rpms drops and it idles ok. I hope I described it good.

I bought the car couple of months ago, the car was running poor and I replaced these parts for new sparks, ignition wires, coils, intake plenum gaskets, all 16 injectors to FIC injectors, iac valve, both pcv valves, map sensor, I checked all vacuum and sealed or tighten if needed, replaced check valves, so I dont think it is vacuum leak because rpms drop after stop, so maybe some kind of sensor or something?