Just thought I would run this by you guys to get some ideas. Coming home this weekend from school, (about a three hour drive) my truck developed a huge miss. It only happens between 2000-3000 rpms. I was cruising around 80mph when all of a sudden it started stumbling real bad. It would drop a couple hundred rpms and then catch itself. It would buck and ran super rough. When I gave it more throttle, and got it running above 3000rpms, it ran perfect. No stumble or miss. While the stumbling occurred, it backfired a couple times. Wouldn't that mean it was going lean during the missing?

I got about 15 miles down the road from school and realized I forgot my HP tuners USB to OBDII. So I couldn't plug the scan tool up and see what was going on. Now I have another three hour drive back not knowing what is happening.

The miss only happened for about 40 miles out of the 200. It did it for about twenty miles in the middle of the trip, then it went back to running fine. About 20 minutes later, it came back and then ran fine the rest of the time. Any ideas?

I will check the spark plug wires tomorrow and anything else I can to diagnose it. Let me know what you think. Thanks guys!

 

Im haveing the same problems exactly. When it happened the first time it started missing and backfiring. Then it just died the gauges were going crazy and the battery not charging was displayed. I wiggled some of the wiring, battery cables, gound wires and it started right up. It has ran fine for 500 miles and i figured it was just a loose cable. This morning it did it again but a little different. It was missing and back firing and died the gauges were normal this time and no codes. It started up and stumbled for about 5 miles and started running fine. Now i cant get it to do it again. I checked all grounds, coil packs, ect, and still nothing.
Maybe someone can shed some light on our problem.

 

Burnt plug wire?

 

Found my problem after I had some light to see what I was doing.

 

Ouch! Glad you found the issue.

 

Do you know what wires those were? Good that you found it.

I drove my truck all weekend and it never missed. I have the three hour drive back tonight so I will see how it goes. I checked all the plug wires and they all looked brand new. I have no way to check the coils until I have my tuning software. So hopefully it runs fine back to school and then I can scan it all this week and see what is going on.

 

I don't have a clue. I just replaced the damaged sections. Its in the same small harness that goes to the temp sensor behind the pos battery connection. Good luck on your trip.

 

Thanks man!

 

Alright, I made it back. It missed again, almost at the exact same spot it did last time. Except this time, it only did it for about 5 miles. Then it was fine the rest of the drive. I got home to my HPT cable and scanned a P0300 code. So that will explain why the converter didn't lock the entire drive down and back up. Good thing I have a 40K cooler. Fluid temp was only 142 degrees. I cleared the misfire code so this week I will try and do some highway driving to find out what is going on.

 

Well I drove it the past couple weeks in town with zero issues. I came home again for thanksgiving break and it missed again. Its always about 90 miles into the drive. This time it did it more than usual. When I got into Vegas, it started missing again so I pulled off and hooked the scanner up. I saw zero issues in the log. It didn't go lean or rich while I felt the miss. Timing didn't spike or move at all. Everything looked great. So now I'm even more confused.