Just bought my 2nd XJ and it won't start. I'm getting fuel pressure to the rail but no spark from the coil. Could it be the elusive crankshaft position sensor or the other CPS? Also, I've seen different posts on the location of said crankshaft position sensor and the mind is blurred. Is there any way to bypass this PITA sensor? Help is much appreciated.

 

No way to bypass any of these sensors. The crank sensor is indeed a primary suspect. But so is your ignition coil. I'd start by testing both of these components, although know that testing of the crank sensor is not always conclusive. Coils can be tested for both primary and secondary resistances with a meter and a service manual.

If you end up replacing the crank sensor, do yourself a huge favor and buy a MOPAR sensor directly from Jeep. Aftermarket crank sensors are very "hit and miss" with a lot of miss.

 

Ok. Replaced sensor and it fired right up. After about 5-10 mins of running, it shut off. Traced wires and it seems that the positive wire for sensor had rubbed a bare spot against the plastic harness on top of injectors along with a ground wire. They seemed to have been close enough to cause a short. Could that short cause that sensor to go bad again? Also, I'm getting 7.2 volts from that positive wire from ECM. Is that normal voltage?