Hope someone can help me with this issue.
1995 XJS 4.0
The car has high rev upon startup (1500+ RPM) and stay there. I have waited up to 15 minutes and it doesnt drop. I had to manually close the butterfly and it settles to 700. I get in the car give it a little gas and it goes up again (say 1200); give it a little more gas and up again to 1800; it always going up but not coming back down. I then force to close the butterfly (on top of TB) and it settle down.
I had cleaned the TB already. Could it be the Idle Control Valve (Stepper motor) is bad?

As I was taking out the ICV, I snap off both of the bolts
A machine shop closeby luckily was able to help drill it out after me spending 2 hours unsuccessfully.

 

There is also a sensor on the bottom of the TB, which I assume is the throttle position sensor (TPS)? Can that be bad? That part has a Ford logo on it .