Ok, Ok, I Know I've been gone for a while... but HELP
#11
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I learned recently that I wasn't checking fuel pressure right also. Do you have the FSMs? There'* a specific set of tests you need to do in order to verifiy proper Fuel Pressure.
Decided to just list it.
From the 95 FSM:
Connect Fuel Pressure Gauge
Make sure ignition is off for at least 10 seconds (AC should be off too)
Switch ignition to "On" Fuel Pump will run for about 2 seconds. It may be neccessary to cycle the ignition on more than once to obtain maximum pressure.
Note the fuel pressure while the pump is running. The pressure should be between 41-47 PSI for L27 or L67, 48-55 for L36. Your pressure might vary slightly and then hold.
If you're pressure is steady and HOLDS, you're GTG.
If pressure is NOT in range, you have a bad fuel pump or fuel pump seal
If pressure is in range but slowly drops off, there'* another series of tests you need to follow but it requires some extra hardware. BillBoost gave me a kindasorta workaround for this:
Cycle on and off about 15 times to really load up the rail and start your car. If it sounds like crap when you're starting, you might have a problem with an injector seal, or something else up top.
Also, pull the vacuum from your FPR and see what your pressure jumps to? If it pegs >41, the FPR'* alright.
Decided to just list it.
From the 95 FSM:
Connect Fuel Pressure Gauge
Make sure ignition is off for at least 10 seconds (AC should be off too)
Switch ignition to "On" Fuel Pump will run for about 2 seconds. It may be neccessary to cycle the ignition on more than once to obtain maximum pressure.
Note the fuel pressure while the pump is running. The pressure should be between 41-47 PSI for L27 or L67, 48-55 for L36. Your pressure might vary slightly and then hold.
If you're pressure is steady and HOLDS, you're GTG.
If pressure is NOT in range, you have a bad fuel pump or fuel pump seal
If pressure is in range but slowly drops off, there'* another series of tests you need to follow but it requires some extra hardware. BillBoost gave me a kindasorta workaround for this:
Cycle on and off about 15 times to really load up the rail and start your car. If it sounds like crap when you're starting, you might have a problem with an injector seal, or something else up top.
Also, pull the vacuum from your FPR and see what your pressure jumps to? If it pegs >41, the FPR'* alright.
#12
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I was just hooking up the gauge and watching FP at idle, and with a load. I dont have a long enough hose to check it while i'm driving.....
Oh yea....I can't duplicate it while i'm checking fp lol... It'* really annoying.
Oh yea....I can't duplicate it while i'm checking fp lol... It'* really annoying.
#13
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Look at my last post again. I listed the basic procedure from the FSM. You don't need the extended hose to test the fuel pressure (tho it really is helpful).
Oh yeah, the cheap and obvious: When'* the last time you checked your fuel filter? Its possible that you might have a weak pump that is being put over the edge by a potentially clogged fuel filter.
Oh yeah, the cheap and obvious: When'* the last time you checked your fuel filter? Its possible that you might have a weak pump that is being put over the edge by a potentially clogged fuel filter.
#14
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As Cheeto said..I doubt his fuel pump is resetting from a cycle of the ignition key.
And after you hook up a fuel pressure gauge you need to bleed the air out. Then test FP.
Otherwise the air can get compressed and mess with your readings.
And after you hook up a fuel pressure gauge you need to bleed the air out. Then test FP.
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My wife'* 2001 Grand Prix was doing something similar, it would cough and sputter on heavy accelleration and it turned out to be a plugged catalytic converter. Just wanted to mention this as a possibility you might want to check just in case.
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