My 88 Iroc 305 TPI has problems starting. It cranks for a while then starts. Sometimes shorter, sometimes longer. Can't find any common ground with the occurances. So I took it to shop for a fuel pressure check. They said when you first start cranking you get around 10 PSI and then when the car starts you have 40 PSI. Then he said i wasn't getting enough voltage to the pump and that there was a code 54. The car always starts just it takes a little while. So i figured, what's 15 bucks and bought a new fuel pump relay. Didn't fix the problem. The pump sometimes stays on for a long time after the car is off. Sometimes hours after. havn't checked for this since the new relay. My dad thinks it may be a faulty ecm. I hope not. Anyone had this problem? Any ideas on how the diagnose it?

 

Yeah, I've been messing with this problem for about a month or two now. I'll have it fixed this weekend, at least I hope so. From what I can tell, the problem was my fuel pump relay harness. My fuel pump relay harness was trashed. All the wires were nearly pulled out and it just wasn;t making a solid connection. Yeah, I've chased it for a while so the relay, pump, and all that has been replaced. I'm probably going to end up having to replace the ECM as well. As for the car taking an extended period of time to start...my car has been doing that since i bought it a year ago and everything on the car has been replaced and it still does that so I don;t think it;s related to your problem. You can take a look here too, may give you somce other places to look:

http://www.iroc-zpost.com/ubb/Forum2/HTML/001044.html


http://www.iroc-zpost.com/ubb/Forum2/HTML/001087.html