2000 S10 Bravada won't start
riverat440
05-29-2009, 05:15 AM
Hey all, I have this vehicle over to help out a friend. It has the 4.3 W engine auto 4x4 which won't even try to start unless it is given a shot of carb cleaner, then it sounds good til the fuel runs out. I'm getting 63psi fuel pressure but didn't do actual output test with the return pinched. I am getting 12v to the injectors with the key on and no pulse when cranking. The security light also goes out after a second or two when turning the key on. I did a search only to find many similar problems but many of these never went far enough to help with my situation. Seems to me the PCM is the problem but have a problem buying parts without being able to properly test the old ones. Any help will be greatly appreciated as I just keep thinking there may be something I am overlooking.
Well I did a little more testing today and found there is a pulse signal using a noid light. The fuel pump pressure is 63psi when you turn the key but drops back to 53psi when the pump stops running. When it is cranked the pressure goes back up to 63psi. I can't seem to find a good place to pinch off the return line so I still haven't been able to check that. Also my friend cranked on it so much he killed the battery so there aren't any codes to read. I guess I am going to replace the fuel pump, it seems to be the only thing logical.
Well I did a little more testing today and found there is a pulse signal using a noid light. The fuel pump pressure is 63psi when you turn the key but drops back to 53psi when the pump stops running. When it is cranked the pressure goes back up to 63psi. I can't seem to find a good place to pinch off the return line so I still haven't been able to check that. Also my friend cranked on it so much he killed the battery so there aren't any codes to read. I guess I am going to replace the fuel pump, it seems to be the only thing logical.
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