Hey guys. Im new to the forums, but in need of some serious help. I have a 95 s10 pickup, vin W, with a 4.3 vortec motor and automatic transmission. The original motor siezed up so i got another from the junk yard and had a mechanic at a shop swap the motor and he took my top half off and swapped it to the new lower half which took him forever. It was supposed to be smogged and ready for me to just put my current tags on it and go, but scan tool will not link up with the computer. I was not happy with all the run around he gave me so i decided to take the truck home and deal with it myself. Truck starts and runs and drives but has absolutely no power and takes forever to even remotely start moving when you press the accelerator pedal. Obd2 has 12 volts and ground and powers up my mac handheld scanner but will jot link up to the computer. I checked for voltage at the computer on the 4 pin plug on the bottom section of the computer that has a brown, purple, heavy guage red wire, and an orange wire in it. No constant 12 volts from the thick red, nor the orange wire. Stumped, cause to my understanding the truck should not be running if im not getting voltage to the computer. Any help would be greatly appreciated. Sorry for the long explanation, but wanted to give you guys as much info as possible so that your time wasnt wasted with back and forth questioning. Thanks in advance.