History of engine and tranny were from a wrecked truck I own I still have the complete truck. I had just changed engine oil and changed the tranny oil before I installed it. I started the engine several times on the original truck with the modified PCM and worked fine once I removed and installed it in my c10 I had problems with the engine idle and engine start up once I would shut it off, it wouldn't restart until the next morning. By then my fuel pump died and that's when I ran into all these issues.