Well, after 2,000 miles, my truck decided it wanted to go in to limp mode and recreate all of the same problems over again after she got all fixed up. I was in a car wash, and couldn't let the truck sit still for any amount of time- it would keep putting itself into limp mode. I would turn the truck off, and restart it but to just have it go to limp mode again. Now, if I were to start driving, she would run fine. conversely, if I slowed down too long; limp mode. Frustrated, I called a friend of mine and he hooked his code reader up to the truck. P1299. Which states low coolant, not an issue-full tank; faulty thermostat, brand new when we just changed the CHT and plugs; faulty CHT, hopefully not we just just replaced it with a brand new OEM one; Cylinder Head Temperature Sensor harness is open or shorted, now wait a minute, better check over all of that.

We found a wiring harness that was not in the correct spot (that is, the "button" that is on the harness was not pushed into the metal bracket it was supposed to be attached to) and therefore was rubbing up against an aluminum piece (couldn't tell you what it was for). It had been rubbing so long that the aluminum piece was worn down some, and the thick cover of the harness was also worn away to barely expose a couple of wires. We covered up the aforementioned wires, and replaced the harness to its correct spot on the metal bracket. We also zip-stripped another part of he harness up for good measure.

Left the truck sitting still at idle and lo and behold; no issues. Truck is back to normal and running fantastic.

I called to mind why it took so long for this issue to reappear. Then it struck me- we had moved around a lot of things when we took the intake off and replaced the plugs. So the wiring harness was moved around, and finally came back to rubbing on the aluminum piece and shorting out.

Hopefully this finally fixed the issue. Time will tell.

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