92 fuel pump question
05-26-2016, 06:10 PM
#1
92 fuel pump question
We gotta 92 that was just in a shop so their saying the pump is at around 20 psi and should be up around 40
The problem in question is sometimes when the cars been running and I shut it off leave for awhile and restart itll miss and and fart the couple minutes later it smooths out and runs fine............the problem doesn't happen often but does happen.
what I wanna know is why does the car start and run fine 90% of time if the pump is said to be going out and have that low of reading??
The problem in question is sometimes when the cars been running and I shut it off leave for awhile and restart itll miss and and fart the couple minutes later it smooths out and runs fine............the problem doesn't happen often but does happen.
what I wanna know is why does the car start and run fine 90% of time if the pump is said to be going out and have that low of reading??
Last edited by lectroglide; 05-26-2016 at 07:22 PM.
05-26-2016, 06:29 PM
#2
Pro
I have no idea what a 20% or 40% pump means. The question is: "can the pump maintain rated pressure under full load?" If yes, its good to go and if not, a new pump and strainer are in order. I'd say that you should find a shop with a pressure gauge that can be hooked up and read while the car is being driven and see if your set up will maintain about 41-47 psi. If not, the fuel system needs attention.
Last edited by 1984Z51auto; 05-26-2016 at 06:31 PM.
05-26-2016, 07:30 PM
#3
I have no idea what a 20% or 40% pump means. The question is: "can the pump maintain rated pressure under full load?" If yes, its good to go and if not, a new pump and strainer are in order. I'd say that you should find a shop with a pressure gauge that can be hooked up and read while the car is being driven and see if your set up will maintain about 41-47 psi. If not, the fuel system needs attention.
Last edited by lectroglide; 05-26-2016 at 07:32 PM.
05-26-2016, 09:08 PM
#5
and get a fuel pressure gauge on it.
05-26-2016, 11:09 PM
#6
Team Owner
We gotta 92 that was just in a shop so their saying the pump is at around 20 psi and should be up around 40
The problem in question is sometimes when the cars been running and I shut it off leave for awhile and restart itll miss and and fart the couple minutes later it smooths out and runs fine............the problem doesn't happen often but does happen.
what I wanna know is why does the car start and run fine 90% of time if the pump is said to be going out and have that low of reading??
The problem in question is sometimes when the cars been running and I shut it off leave for awhile and restart itll miss and and fart the couple minutes later it smooths out and runs fine............the problem doesn't happen often but does happen.
what I wanna know is why does the car start and run fine 90% of time if the pump is said to be going out and have that low of reading??
When you cycle the pump and let the pressure bleed off, are the plugs wet with fuel? If so, time for the injectors to be serviced or replaced.
Could your pulsator be leaking? Hard to tell from here but if you clamp off the return line and the pressure drops and the plugs are dry, I would suspect the pulsator.
The low reading could be bad fuel pressure regulator, leaking injectors, leaking damper or a combination of all 3. Reason it runs well most times is that you are not always demanding full fuel volume and pressure.
05-27-2016, 05:47 PM
#7
And what else have they done? Any fool can hook up a gauge and say "30 psi". If it were mine, first thing to check is if the fuel pressure hose were removed, does it smell of gas. If so, you have a ruptured fuel pressure regulator diaphragm and before I go anywhere, I change that. I would also crimp off the return line and see if it holds pressure. If it does, your regulator diaphragm might have issues.
When you cycle the pump and let the pressure bleed off, are the plugs wet with fuel? If so, time for the injectors to be serviced or replaced.
Could your pulsator be leaking? Hard to tell from here but if you clamp off the return line and the pressure drops and the plugs are dry, I would suspect the pulsator.
The low reading could be bad fuel pressure regulator, leaking injectors, leaking damper or a combination of all 3. Reason it runs well most times is that you are not always demanding full fuel volume and pressure.
When you cycle the pump and let the pressure bleed off, are the plugs wet with fuel? If so, time for the injectors to be serviced or replaced.
Could your pulsator be leaking? Hard to tell from here but if you clamp off the return line and the pressure drops and the plugs are dry, I would suspect the pulsator.
The low reading could be bad fuel pressure regulator, leaking injectors, leaking damper or a combination of all 3. Reason it runs well most times is that you are not always demanding full fuel volume and pressure.
but your right about when I put my foot in it does bog down , BTW what does the "pulsator do?
Last edited by lectroglide; 05-27-2016 at 05:50 PM.
05-27-2016, 06:02 PM
#8
05-27-2016, 06:22 PM
#9
[QUOTE=antfarmer2;1592304355]It connects your pump to the fuel line. If they leak you have a fountain in your tank and low fuel pressue.
[/QUOTE
ok thanx and am hoping after we pull the pump out that will be the culprit, but might as well get a new pump and replace the whole works
[/QUOTEok thanx and am hoping after we pull the pump out that will be the culprit, but might as well get a new pump and replace the whole works
Last edited by lectroglide; 05-27-2016 at 06:24 PM.
05-27-2016, 07:38 PM
#10
Team Owner
Start with the basic testing before we toss parts at the issue. If you have to, get a kit from Racetronix which will take care of the pulsator and get you needed new bolts and gasket with no trips to the hardware store or the dealership