Fuel Pump...?

[blindeyed]

So, I know quite a few of you on here have had to change out your fuel pumps. Just wondering, what were the signs/symptons you had that led you to conclude it was in fact your fuel pump. Right now I'm thinking mine may be on it's way out. For a few months now, when I start the car when it's cold, there's this annoying grinding sound coming from my hatch. It doesn't do it when I get movin or once the car's warmed up, but sitting still while it's still cold, you can clearly hear it. And lately, after sitting overnight, when I go to start it, it misfires until I get out my driveway and get moving. And finally, sometimes when I go to reverse to back out of a parking spot or whatever, and then put it in drive, if I don't give it enough gas it feels like it's about to stall out. And I know it's not the fuel filter, because I just changed that sucker out thinking that was it. So, anyone?

[SG007]

Well, to tell you the truth, you really won't know for sure until its died. lol It's just the way it goes..

[Morley]

Pressure test is the only sure way to tell if the pump is ok or not.
Not sure how the 4th gens are plumbed, but on the 3rds you clamp off the return hose, turn the key and check the pressure. The pressure should be dead headed and read around 75 PSI. Next, you need a helper to turn the key on and as soon as the pump stops running you clamp off the supply hose. If it is an LT1 engine you should see about 43 PSI. If it is an LS1 you should see around 58 PSI. If during the first test you have a rapid pressure drop off, but not during the second test, the check valve in the pump is bad. If you have a rapid pressure loss on both tests, either the regulator is leaking or injector(s). Pull the vacuum line from the regulator and if there is gas there, the regulator is bad. No gas at the regulator...leaking injector(s).

[blindeyed]

Originally Posted by Morley

Pressure test is the only sure way to tell if the pump is ok or not.
Not sure how the 4th gens are plumbed, but on the 3rds you clamp off the return hose, turn the key and check the pressure. The pressure should be dead headed and read around 75 PSI. Next, you need a helper to turn the key on and as soon as the pump stops running you clamp off the supply hose. If it is an LT1 engine you should see about 43 PSI. If it is an LS1 you should see around 58 PSI. If during the first test you have a rapid pressure drop off, but not during the second test, the check valve in the pump is bad. If you have a rapid pressure loss on both tests, either the regulator is leaking or injector(s). Pull the vacuum line from the regulator and if there is gas there, the regulator is bad. No gas at the regulator...leaking injector(s).

Morley, I regretfully inform you that I have no idea how to do any of that