Problem with fuel system after Heads/Cam swap (LT1)
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Problem with fuel system after Heads/Cam swap (LT1)
I pulled my motor to do a Heads/Cam swap - when I put it all back together it fired right up. After running for about 10 minutes, it wouldn't idle right and wanted to stall. 30 minutes later I couldn't get it to start at all. I put a fuel pressure gauge on it and only got 17PSI KOEO. Even after a couple ignition switch cycles it wouldn't go any higher. I went back two days later to take a look at it, and it started right up - but wanted to stall right away. Put the FPG back on it and only registered 10 PSI.
Jumped the fuel primer lead, and didn't get any additional pressure. Starting the motor with the FPG on, it showed an immediate drop from 10 PSI towards zero.
I haven't put it back on the lift yet to check the power at the pump, but I'm pretty sure I can rule out the injectors and FPR. Right?
I'm not sure why it would have failed right away, it only has 74K miles and ran perfectly. It has a full tank of gas, and I did a PCMforless tune which accounted for the bigger TB and 42# injectors.
Any experience with similar situations?
I'm thinking about a racetronix kit if the FP is indeed bad - but I don't want to spend another $200+ if that's not the problem.
Thoughts??
Jumped the fuel primer lead, and didn't get any additional pressure. Starting the motor with the FPG on, it showed an immediate drop from 10 PSI towards zero.
I haven't put it back on the lift yet to check the power at the pump, but I'm pretty sure I can rule out the injectors and FPR. Right?
I'm not sure why it would have failed right away, it only has 74K miles and ran perfectly. It has a full tank of gas, and I did a PCMforless tune which accounted for the bigger TB and 42# injectors.
Any experience with similar situations?
I'm thinking about a racetronix kit if the FP is indeed bad - but I don't want to spend another $200+ if that's not the problem.
Thoughts??
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Most likely its the pump but it could be the reg. not holding the pressure back. If you could stop it up before the reg. and have the gauge inline you could check that the pump makes high pressure without the reg. inline. If it does not its the pump.
Nate
Nate
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Or you could just crip off your return line and that should cause a pressure spike of over 100psi. If not you know your fuel pump is bad. If it shoots up to 100psi you know the pump is good and the reg is bad.