I have a small dilemma, one that has a simple answer I’m sure. I have a 2004 ENVOY 4.2 engine. I wanted to basically go thru it from top to bottom and have due to some old, worn out parts. My son a…

GMC Envoy BBQ

I have a small dilemma, one that has a simple answer I’m sure.
I have a 2004 ENVOY 4.2 engine. I wanted to basically go thru it from top to bottom and have due to some old, worn out parts. My son a very responsible and thorough young man who recleans and reorganizes the tools after I leave the shop. He has an I.Q. over a hundred and was helpin me at the end of the day. However, when his little girlfriend shows up, I would compare his intelligence to that of a potato chip. So without telling me he had MISPLACED said TB. He went to the pick a part and replaced it with a different one. He also removed and took the gas pedal with him to the scrap yard. Girlfriend loyally by his side they forget to take it with them when they left. So, he gets home and realizes that he left said pedal. It was too late. They closed. The next day after school, he goes back to pick a part and can’t find original pedal. So buys another pedal out of an 06 or 07 cleans it up and replaces it without saying a word. After I put it all back together, I’m getting engine codes thrown at me from all directions. Finally, after I’ve pulled al my hair out I discovered his little secret. So in order for me to drive that car, I have to take a jumper wire and ground the purple wire from the gas pedal back to the firewall for it to stay out of reduced engine mode. Check engine light flashing it’s ass off, the car will throw It’s self in the reduced engine mode while driving down the highway. I have to put the car in neutral while driving turn the key off and start the car while in motion slip it back in the drive and keep driving.Meanwhile the car is running terribly. I was told that I needed to re-calibrate both throttle positioning sensor and pedal position sensor and have my ECU flashed.My dilemma is I cannot afford the $120 it’s gonna take to flash the ECU. I need an inexpensive ECU flasher. One that’s under like 50 bucks that will work to reflash my ECU. However I know little to nothing about these things so any suggestions or any recommendations would be very appreciated.