My 93 jeep grand cherokee 5.2 V8 lately has not been idling up to spec. The Check Engine light comes on and the engine has a hard time starting(have to floor accel.) and once started, wants to quit and keeps revving by itself. I tried to back up once and it just stalled!:banghead: There is also sometimes bits of black residue coming from exhaust, any ideas? Also when I push the gas to go forward, it lopes and doesn't want to go for a few seconds.:screwy:

Thanks for your help!

TPS comes to mind. Pull fault codes with the ignition on/off method.

You might also wan to check the coolant sensor.
Had similar problem and found the coolant sensor was way out but the guage seemed to operate normally.

pull the codes out of it and try cleaning the throttle body you also may have a leaking injector

Found out it was bad coolant sensor, runs great now

Thanks