ECT Sensor Question

[RYanmas9]

Ok guys,
Bought a 2002 Ford F250 4x4 6 speed with 155K back in August. She had some issues but I am slowly getting them fixed. Up Pipes were leaking, exhaust had been done by some first time welder that was blind folded....ect. My check engine light was on of course. So I have replaced my Up pipes with the International Beveled pipes, and have a new 4" turbo back exhaust. She is sounding good and running like a champ. Pulled the codes and showed P0117 and P0476.
P0476 Was the Exhaust Pressure sensor. It was pretty much full to the brim with carbon, so replaced that and cleaned the tube out. Now the Valve in the turbo works and my fuel mileage has increased. Had some starting issues so also replaced CPS and ICP sensors. Had the fuel heater wires rubbing together shorting out. Spliced the plug and fixed the wires. Fixed all those problems.
My problem lies with the P0117 Code. This is the ECT sensor. I replaced the ECT sensor and it is showing normal temps. Whenever the truck gets into normal operating temperature the CEL comes on. Once the truck is shut off and cools down the light goes back off. Thinking it might be something else, I replace the Air intake sensor at both the Air intake and the Air charge sensor on the Spider Pipes up by the turbo...still got the light. I unplugged the sensor and the temperature gauge goes to the cold range...so Im guessing there arent any wiring shorts.
I've read that the manuals go by the Engine Coolant temperature while the automatics go by the Engine Oil Temperature. Is this true or could my oil temp sensor need replaced? Im lost guys I dont know where to go from here. Any ideas? MAP sensor tied to this at all?