how to check fuel psi
- Thread starter westridez
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the stock fuel pressure should be between 38 and 42 psi. you can not adjust the fuel pressure with the stock regulator.
there is a schrader valve behind the alt on the pass side fuel rail (it looks like a tire valve). be real careful when connecting and testing - fuel will squirt out while connecting and disconnecting and if the connection is bad, you can have a fuel leak.
good luck.
good luck.
i would use a fuel pressure gauge (stop right now - i can see you walking toward the tire gauge, figuring it will work. LOL). it will work in a total pinch, but i think having a diagnostic FP guage is a good thing to have in the tool box. they are 30 bucks or so at parts stores.
the gauge i got has fittings for several types of connections, including an adapter for the schrader valve on your stang.
good luck.
the gauge i got has fittings for several types of connections, including an adapter for the schrader valve on your stang.
good luck.
88_GT_5_oh
Sportin' a turbo 5.0 in Canadistan
HISSIN50 said:
lol i thought the same thing...... it really is a good i dea to pick on eup, mine also came with lots of different fittings, and i have used it on a number of cars, it is a good tool that can tell you right away if you are getting gas or not
Check with the car on engine running. Hook it up before you run the motor though. I always make sure the gas has evaporated before I turn the motor over. Pull off the vacuum tube from the FPR and it should read approx 40 psi. Then turn your car off and purge the gas from the gauge (should have a long clear tube with a black button on the side. Press the black button with the clear tube vented as far away from the car as you can) thats how you check it.. good luck..
When checking fuel pressure, hook up the gauge to test port with the car off. Then turn the key to the "on" position. The pump should prime and the pressure should go up to about 40-45 psi. This pressure should hold steady even after the pump stops priming. If the pressure starts to fall, then the pressure regulator could be bad or the regulator at the pump could be bad. Or in extreme cases, there could be a leak. Start the car. The pressure with the engine running will usually read a bit lower (about 5 psi) then with the car off. It should go up when the vacuum line is pulled off.westridez said:
Fuel pressure testers come in all kinds of varieties. I paid $330 for mine. This is overkill for an amateur or a DIY guy. You can get a cheap parts store one for maybe 20 bucks.
88GT socal, it seems to me that you are in the business (based on your posts and why one might have that $$ tester). i have not seen anything nice like that - what are the good things about a tester like that?
Before you hook up the gauge, start the car, and then pull the connector off the intertia switch in the trunk. The fuel pump will stop running, and the motor will die from lack of fuel. This removes and pressure in the line limiting how much gas will spray back in your face. Make sure the reconnect the switch of course. 
gotcha bud. sounds like a nice piece (and probably real nice for cars with no schrader valve. making tees for banjo bolt fittings at fuel filters, etc is not cool.88GTsocal said:
). thanks for the info. 
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