When im sitting in park, reverse, or drive sitting still my zj idles low and shakes alot, i have to hold the gas and brake at stop lights to stop shaking. Ive been told it might be the motor mounts( they were good) and also the Throttle body sensor. any ideas?
I believe you mean the throttle position sensor. Yes, it could be, but i would clean the IAC good first.
You can electrically test the TPS:
The TPS (Fig. 59) can be tested with a digital voltmeter.
The center electrical terminal of the TPS is
the output terminal.
With the ignition key in the ON position, check the
TPS output voltage at the center terminal wire of the
connector. Check this at idle (throttle plate closed)
and at wide open throttle (WOT). At idle, TPS output
voltage should be greater than .350 millivolts but
less than 900 millivolts. At wide open throttle, TPS
output voltage must be less than 4.5 volts. The output
voltage should increase gradually as the throttle
plate is slowly opened from idle to WOT.
PO did about 1-2 yrs ago but maybe used cheap parts... i only replaced spark plugs cuz i noticed autolites and i replaced wit champion. i also did 02 sensors... maybe i should just get new wires cap and rotor and coil as well huh? what about the distributor pick up? how do u know if that is going bad? any symptoms im having as a result of it going bad?