Perhaps the throttle plate is stuck - try to free with a screwdriver
sounds like a bad idle control sensor
the iac motor is faulty replace....(automatic idle control) easy fix 2 bolts and 2-3 wire connections.
all idle speeds arfe controlled by the computer and are not adjustable.
probably a bad idle air controller.
try adjusting the ignition timing(or getting a mechanic to do it)
It is very likely there is no way to adjust the idle on your car. If your car is idling low, it's probably a problem somewhere else. Idle is likely controlled by the computer.
water pump or thertomstat
The Throttle body is where all the sensors are for this car. If your having an Idle problem though, It is rarely that.
Check Related Link below. It shows you a picture too.
!t can be the air flow censer it might be messed up or the rong one usually the rong one will make it idle high.
there is no "fast idle solenoid" there has'nt been a fast idle adjustment on passenger cars in over 20 years
The fuel pressure for an 89 Ford F250 with a 5.8L MFI is between 13 and 20 psi with the engine at idle. With the key on engine off, the gauge should read between 23 and 31 psi.