2000 blazer ZR2 how to you do a learn procedure?
#52
More diagnosis is necessary, unless you want to guess Could be a regulator, could be a pump, we don't know for sure yet. Key ON, engine OFF, fuel pump running: pressure was 50psi? If that's correct, pressure is too low. What was the 45psi "cranking"? No cranking involved when testing fuel pressure. What was the pressure 10 minutes after the pump shut off?
Next step is check maximum fuel pump output pressure at the fuel filter. The pressure tester will need to be modified so it connects directly to the fuel line from the pump, and dead ends, (no fuel flow allowed past the tester).
Next step is check maximum fuel pump output pressure at the fuel filter. The pressure tester will need to be modified so it connects directly to the fuel line from the pump, and dead ends, (no fuel flow allowed past the tester).
#53
Yes 50 and then it was 45 if you try and start it. Didn't check after 10 min cause It was already very low. Also can't modify the gauge it is not mine to modify.
Last edited by david068513; 08-27-2012 at 08:26 PM.
#54
To determine exactly what the problem is, without guessing, max output pressure must be tested. You can build a tester for around $40 that will test regulated pressure, max output pressure and determine if leakdown is excessive, and where it is. Here's an image of one that I built a few years ago:
#55
I can't modify the gauge. I really don't want to go buy one ruin it either to but use it for other things either. It's a 50 dollar gauge and and 90 after modified. I ordered all new lines, regulator, etc for under the intake.
#57
I can't modify the gauge it is not mine and I'm not spending 90 dollars to make one I can only use for one thing. The whole spider setup was 100 bucks and the fuel pump os under warranty so I'm spending the same money as making the tool no matter what is wrong
#59
Changed the whole spider setup. Had 52-55 psi and would run and drive and start during that day. Left it running for 30 min and it studdered and died and would not restart again. I don't under stand why it would start and run and that not be a fix to the issue, I'm changing the fuel pump again and seeing if that helps cause it is free. People keep telling me to change the dist. It has spark i pulled a plug but they said it will text fine but it is the issue, could this be true?
#60
52-55 psi is far too low. Needs to be 60psi to 66psi. You need to check maximum fuel pump output pressure at the fuel filter to make sure the pump is working properly. If pump output is low, pressure at the service port will be low. What brand fuel pump did you install? Don't waste your time installing another aftermarket pump, eventually you'll get tired of replacing it.... get an AC Delco or Delphi pump and be done with it. Pay the difference to upgrade, most good auto parts stores will accomodate you.