Hello, I'm a new user from Buenos Aires, Argentina. I have a '02 Grand Cherokee 4.7. About a couple of weeks ago started to stall every now and then, most of the time when cold, I changed the IAC and then the cold idle problems were gone. Now, after driving about 20 minutes, starts to stall when stoping at the red light. It has no problem to start again, but, when I put it in Drive after doing it, most of the times stalls. The same happens when reversing. I hope you can help me. Thank you!

 

I would check your Throttle Position Sensor (TPS), then check your fuel filter, and then your O2 sensor.

 

Thanks! I'll check them all. Checking the engine bay fuse box found there was no o2 sensor fuse, I'm going to put one in there and test it. Also, I did the key trick to see if there was any code and two appeared. P1391 and P0700. I ordered myself a CKP and see if it solves the problem. Can be the P0700 caused also by a faulty CKP? Or they are two different problems? I'll post how it goes with the new crankshaft position sensor

 

I would go look again to the IAC motor. More than once Ive had aftermarket ones go bad very quickly. Cheapo parts

 

That fuse for the 02s is for the heater circuit that preheats them to make them function quicker. It's possible it's shorted to ground as well as to a sensor itself. That sometimes happens if the wiring touches the exhaust pipe and melts the wiring together.