Engine runs good *** when I press the clutch in, engine revs. For example, if I shift at 3500 RPM's engine will rev to 4000 RPM's when I press the clutch in. If I let off the accelerator pedal, it stills has throttle for about 1-2 seconds. Checked for vaccum leaks, have found none, no binding in the throttle cable either. Please help me out.

 

Whats the problem? the engine is reving without you pressing on the throttle?

 

Foot off the throttle and the clutch pressed, engine revs. Adjusted fast idle valve, made no difference.

 

the thing that causes the rpm to rise is the IACV. The iacv is used to regulate rpms when the engine is under a workload .. things like A/C, Headlights, radio, etc. buts it's also used to smooth out injector transitions(shifting gears)

u can disable the IACV, but shifting, esspecially at higher gears and rpms will be pretty rough.

I've also heard of building a home-made gasket to close up the IACV ports a bit. Because they ports are made a bit Larger then needed in our cars.