I have a 1992 Chevrolet C/K1500. In 2004 I built a 383 and installed it. At that time I also switch to a 454 TBI and injectors. I had the chip reprogrammed for these changes and added a Walbro 255 lb hr fuel pump and adjustable FP regulator. The truck has never quite ran right. I have made a lot of changes and it has run better but it has always hesitated at WOT and would get hot stopped at a light in the summer. When it would get hot at the light the RPM's and oil pressure would rise and fall dramatically. I assume it is because I never installed a bigger radiator or electric fans. It became a non issue because I moved to an area where there were no red lights between work and home. I worked on the truck and settled because I put my money into my car. I haven’t had any problems until the past few months. While driving the truck I notice the RPM’s would increase by about 400 but engine speed would not. With it being winter the truck never really gets hot but I also noticed it was not getting over 100 degrees. Also the truck would not start sometimes. I switched out my control module on the back of the distributor for the starting issue, which seemed to fix the not starting issues for the time being. For the RPM increase initially I checked the TPS sensor volts and they were low so I changed the switch. This started a whole evolution of issues. The next day the idle was extremely high and white smoke was coming from the exhaust. It did not smell sweet like anti freeze but like the fuel was too rich. There was a faint ticking noise I could hear coming from inside the engine. I could hear it in the exhaust but it would get fairly loud from underneath the truck. I noticed my injectors were not flowing properly. I order some injectors and a gasket kit to rebuild the throttle body. I replaced all the gaskets and packings as well as the injectors. The engine would not fire with the new injectors (they were 350 injectors and I am programmed for 454 injectors). I put the old injectors back in and it started fine. I metered the new TPS sensor and it was at 6.5 volts (which I thought explained the high idle). I reinstalled the old sensor and moved it to get 5.65 volts. As for the truck not reaching temperature I changed the T-stat (I am programmed for a 160 T-stat) and started the truck. Everything seemed fine, temp went up, it idled fine, no white smoke and I couldn’t hear a tick. The next day I was driving to work and it reached 180 degrees and kept climbing. I ended up stopped at a light and it went up to about 220-240. As soon as I took of the temp dropped to 160 and stayed there. When I pulled up to the gym was idling high. In fact the speed limit was 35 and I let off the gas and the speed would not drop. As if it was on cruise control. When the speed limit dropped to 25 I hit the brakes and let off. The speed stared climbing on its own. After I was done at the gym I started the truck and the idle was low. It dropped so low that it almost shut off. I drove to work and the truck was coming back up to operating temp and shot up to 240 again. I shut it off. On my way home the temp shot up again but the idle seemed fine. But when I had to stop at the red light (I have those now) I could hear a faint noise almost sounded like a diesel engine. I feel I may have to issues. For the idle maybe a chip or sensor problem but for the overheating and ticking I feel I have a lifter going bad and a blown head gasket. This is my daily driver but I am getting so close on the car so if the truck can hold out for maybe a month I can use the car until I go on deployment. I have been talking to Sean at TBIPARTS.com and he has been helpful. He is also sending the correct 454 injectors and a new IAC motor. Any additional information anyone can offer would be great.