Help! Jeep trying to kill me!
 

Well, maybe not trying but it might end up doing so. All joking aside I was driving home from work and it started accelerating on its own. Nothing pushing the pedal down, and I don’t have cruise control. 1990 Cherokee XJ 4WD. I have been having some shifting issues that are being dealt with but this is new. I am terrified to drive it anywhere now.

Accelerator pedal getting caught on floor mat ?

take out all floormats, have someone operate the pedal while you check for any binding of parts in pedal or engine throttle mechanism, or frayed/ rusty inner cables etc

Did the behavior change when you used the brakes? (ie. did it stop trying to accelerate as soon as your reacted by applying brakes?)

I've heard cases where the braided cable broke a strand inside the housing of the throttle cable and got stuck in the plastic inner sheath. It used to happen when GM first started using cable throttles because the strands were twisted, not braided.

Just a wild guess but if you’re having shifting and throttle issues then maybe there’s a problem with the throttle position sensor.

TPS will not make the vehicle accelerate. For the motor to run faster it has to be getting more air. That air normally should only come through the throttle body. Controlled only mechanically by the accelerator pedal or when at idle via the Idle Air Control (IAC). But if there is a leak in a vacuum line, or a problem with the intake manifold not sitting flush against the block (or a gasket problem) undesired air can get sucked into the mix and cause the RPMs to increase.