So, I rebuilt my 4.0 about 20k miles ago. I was driving it and everything seemed normal until I gave it some throttle and it started sputtering. It smoothed out and was fine until I got home. I went out to start it about 10 min after the trip on the highway and it revved, sputtered and died at idle. Now a day later it idles for awhile and then dies. If I give it any gas it shudders and dies. Any ideas?

 

Check fuel pressure?

 

Fuel pressure is good. Cam sensor and coil rail codes are showing up on the scanner. Going to try the sensor first

 

Sounds like a good place to start.

 

If you have a rusted muffler and/or catalytic converter it can plug up the exhaust gasses and cause you all kinds of havoc. Happened to me.

 

There is nothing in stock locally. Just ordered a mopar cam sensor, an airtex viper coil, a patch cable for the coil and a universal plug wire set.

 

Exhaust should be good. I replaced all of it when I did the rebuild

 

Check for vacuum leaks. And that belt sounds horrible.

 

It could be electrical too. I had my Jeep sit for a few months while I took my time replacing the front suspension. When I got it running again, the alternator had seized. After I changed it, the old battery wouldn't hold a charge anymore, so it would idle for a little bit after startup and then die.

 

The belt does sound pretty terrible. I'll be taking care of that as well

 

9It's back to life! Replaced the cam sensor and set the timing. I replaced the coil rail with the viper coil and now it seems to be good. Haven't gone on a drive yet because I have to figure out where the coil is going to be mounted