I'll try to make this short, but I need some help and I'm not ready to take the truck to an overpriced mechanic.

A few months ago the truck started running rough, idling ok but dying once you gave it throttle, and then eventually entered Limp mode. It's now throwing a constant code 14. After checking TPS, MAF, and a few grounds, I gave up for a while. I then had to rebuild my starter and while doing that, I replaced the igniter with one from a junk yard. After replacing the igniter, the trucked acted normal for about a week and I was happy. Until one day, it died on the way home from work, showing the exact symptoms as before. Bummer.

Since then, I checked resistance at the pickup coils in the distributor and all checks out. Coil resistance checks out. Grounds for the coil and igniter were cleaned. I don't know if it was a coincidence that the igniter replacement temporarily fixed the issue or if I burnt up that igniter, but I don't know the next logical diagnosis step.

Can anyone offer advice or other things to check?

 

To add some information..

The truck will always start up and run fine until it warms up a bit. It will then change tone, and go into Limp mode (rev limit to 2500 rpm) but still idle normal. Once fully warmed up, it will start to stutter and then die. I checked for voltage at IG2 to ground at the ECM and it checks out. Could something ELSE that's not ignition signal related throw a code 14? I have good ground at the ECM as well.