Diplomat1

Hello all new guy here I picked up a 02 grand Cherokee 4.0 from a friend. Car starts but runs rough. Have codes p0340 p0352. I changed the plugs the coil strip and cam sensor and still no change. I have read online about the wiring harness getting rubbed thru on the back of the motor I checked and everything looks good. I want to test the connector to the cmp and ckp sensors but haven't found any way of testing them. I want to correctly diagnose this problem before throwing any more parts at it. I am hoping you guys can steer me correctly from here on out. What should my next step be? Thanks guys

I also want to mention if I unplug the cam position sensor it's the same as if it's plugged in meaning the car will runs the same weather the connector is plugged in or not. Don't know if that makes a difference

97grand4.0

What are the codes for? How is the fuel pressure?

Diplomat1

340 is cam position sensor 352 is ignition coil b circuit. Haven't checked ful pressure yet didn't think that would help.

Diplomat1

I just came back from checking a couple more things. All the fuses are good in the 2 fuse boxes. I also checked the connector side and had 5 volts on the red wire, 5 volts on the yellow wire and good ground on the black wire with the key on engine off. Is that the way it's supposed to be? I hear the ckp can cause this code I will check that next.

Diplomat1

Just checked the ckp sensor and it looks new. It also has 5 volts to the red wire , 5 volts to the yellow wire and good ground on the black wire. I check for continuity between the red wire on each cmp and ckp connectors and I had continuity. On the yellow wire there is NO continuity between the connectors. Does this sound like a pcm problem? I'm hoping someone can help me thanks

97grand4.0

So you have a code for cam position sensor. Also you said when you unplug it it runs with no change. (not a test I would recommend.) As far as wire colors etc you need a wiring diagram for that. But I would personally start looking hard at the cam position sensor. That bad boy will do just what you describe amongst other things. Mopar only on that one too, same reason, weak magnets on others. I actually pulled one from a boneyard and it works fine for over a year now, nothing wrong with the old one except that the plastic piece was broke. Yours is different than my 97 as you have no dissy. but I would look carefully there, the code is usually right about that one. As far as testing it with an ohm meter, beh, not so sure about that as it may not work. I would go ahead and pull one from a yard. $3. Also pay attention to the shaft, if it has play in it, broken, etc. and the harness and connector