[buffgun52]

I have read alot on this site with similar problems. My 97 TJ with the 4.0 automatic shut down on the drive home. I got it started and drove home and it will not start, but crank all day. It has a new crank positin sensor and a new cam position sensor and a new coil. I have replaced all the relays and checked all the fuses in both PDM's. I have cleaned and checked all connnections. I have good power and ground to the ECM. The gauges are working and there are no fault codes. The fuel pump does come on and there is pressure in the rail. No spark out of the coil and the black/green wire going into the coil only has power for about 2 seconds. Don't know if its the ECM or not. Any Thoughts would be helpful.

 

[buffgun52]

I hope this helps others

I discovered why my TJ would crank but not start. I had no power to the primary side of the coil. I would ohms check it from the bottom side of the PDM to the coil and it would ohms check good but when I would try to start the jeep I would have no power to the coil. What I finally figured out was that just ohms checking the wire it was fine but when a load was applied the voltage was lost. The problem was a plug about three inches to the left of the ecm, a square plug with about 15 terminals in it. This plug contains the green and black wire from the ecm to the coil. The plug and the terminals all looked fine but the connection was bad. as soon as I bypassed the plug with a jumper wire the jeep started and ran like a top.

 

[TexasT]

Excellent trouble shooting. Glad you found it.

 

[composto86]

Nicely done