I changed the cps in my Cherokee and now it don't run right. It didn't fire up good before but now it starts right up. Only thing is, it just don't wanna run good. When I try to get on it, it cuts out and misses. If I drive it like a grandpa it does good. I don't understand what's wrong with it. I also had a heat problem before too. It would heat but only on defrost. Now after changing the cps it blows out of the vents. I don't know if that has anything to do with it messing up or not. Somebody said to unplug the battery for a few minutes and see if that helps it any, I need help!!!

 

Try resetting the ecu. Take off the positive terminal, touch it to ground for 30 seconds, reconnect it, go and put the key in the ignition and turn to the on position (without starting the car!!), turn your headlights on, turn your headlights off, turn the key back to the off position, and then start the car.
See if that makes a difference

 

The crank sensor would have absolutely no affect on your heating issue. You have two things going on.

Where did you buy your crank sensor? There is no lack of threads of people having trouble with aftermarket crank sensors. I buy plenty of aftermarket parts, but the crank sensor is one thing I purchase only from Jeep. Well worth the extra money.

 

I got it from ebay for 19 bucks. I saved 80 dollars but I think I see why now. It made me check engine light come on and when I tested it, it said it was the crankshaft position sensor. I guess I just have a bad part.

 

Lots of junk sensors floating around on ebay. It's generally cheap charlie stuff from China.

My rule is this. NEVER buy anything electronic (especially sensors) from ebay UNLESS it is a confirmed brand name.

Buy one from Jeep.

 

Alright thanks, I will get another one and see if it fixes my problem.

 

Couldn't agree more. Never wanna cheap out on sensors

 

If the screws in the sensor don't get tight enough, would that make it act like it is?? It is starting up just fine but it just ain't running too good.