Hey, today I took my Cherokee to the local carwash to clean up all the mud that was stuck underneath the car and engine bay. After washing the engine, the car started up fine but when I put my foot down on the throttle, it would just turn off. When I try start it up again I would have to open the throttle wide open and it would start. The only to get it revving up would be to open the throttle very slowly and then it would splutter. I made sure there was no water in the air cleaner and I covered the distributer with a plastic bag.

After a while trying to get it going, it just randomly started running fine. This has happened twice now and I would like to find out why this happens.

 

So, after the washing that included your engine bay, this occured. Possibility is your Throttle Position Sensor (TPS) might have caught some water. TPS hates water and given the washing action appearently changed something for the worse, give the TPS a look.
Go over your grounds and connectors as well and check if anything might have dislodged during the washing (connectors, wires etc).
Fuses and relay box dry?