papaindigo wrote:
While if might be part of your problem I doubt it's all of your problem. FYI a bad crank position sensor will not throw/set a code. Only way I know to diagnose is to pull off; hook up volt/ohm meter; apply heat as with hair dryer; if resistance goes nuts it's bad.
A bad CPS can cause random no start; no start when engine warm/hot; or just die and engine won't start no matter what.
I literally just got done dealing with this issue last week.
My 06 would randomly crank but not start unless I let it sit, then it would start and run no problem most of the time. It just died while I was at a redlight 2x over the course of a week then would refuse to restart until it sat for 20 to 30 min. Then it would fire and run like nothing every happened. No engine codes or anything.
I replaced the Cam position sensor and the Crank sensor (which is what I believe to be the culprit) because I figured they are both 10 years old and probably need replaced. Jeep runs fine now and has not failed to start/died since last Thursday when I replaced both sensors.
I would try Crank sensor before you fork over piles of $$$ to dealer to find out no more than you knew before, they will just start throwing parts at it, frequently the wrong one.
The crank sensor is on passenger side of engine just behind the heat shield on the side of the block behind the turbo down pipe. You will need a 10mm socket for the heat shield bolts (2x) and then i believe it was an 8MM socket to take the bracket loose that holds the electrical connector for the Crank sensor as it is impossible to unplug while the bracket is bolted down. You will also probably need a 3in extension. The bolt that holds the sensor can be done with an allen key or socket I cannot remember what size. I did the entire job laying on cardboard with the jeep sitting on the ground, you will pretty much be working using only your right hand so you may have to stop a few times so your hand does not cramp up. it probably took me 45 min to an hour working at a leisurely pace to complete.
These pics from another thread will probably be helpful, there is a closeup of the crank sensor about halfway down the page.
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