95 gt low fuel pressure priming

kevinsivak

New Member
Jul 3, 2012
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I'm in the process of getting my 95 gt up and running After getting my new motor set up. The wire to the starter solenoid wasn't getting any power so I was able to use a screwdriver to get it to start. It ran for about 3 seconds and shut off. I could not see the gauge when I jumped the starter since I was under the car. So I don't know if it raised pressure when it started. I noticed when I primed the fuel pumps the fuel pressure gauge in my fuel pressure regulator only read 20 psi. I've primed the pumps a few more times and the gauge never goes past 20 psi. I did notice 2 small fuel leaks on the lines to the rails by the fittings. i haven't tried to start it since I'm waiting to get the leaking fittings taken care of. My question are... Is it normal for the fuel pumps to only reach 20 psi when they prime for 2 seconds? Should I be looking at the circuit that keeps the pumps running when the car is started? Could my gauge be reading wrong? The fuel system is new it's been installed a few years ago but never ran until now. Should I be checking for a faulty CCRM? Or ECU? I'm just not sure. If the motor fired up and ran for a few seconds could that rule out a few things like the CCRM or ECU? Maybe a problem with the regulator? Any info would be greatly appreciated. Thanks
 
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After and only after you have fixed the leaks, here's the test path for fuel pump and regulator.

Check fuel pressure:
The local auto parts store may rent or loan a fuel pressure test gauge if you don't have one.
Disconnect the vacuum line from the fuel pressure regulator. Check it for evidence of fuel present in the line by removing it and blowing air through it. If you find fuel, the fuel pressure regulator has failed. Reinstall the line; leave the fuel pressure regulator end of the vacuum line disconnected. Then cap or plug the open end of the vacuum line and stow it out of the way.
Connect the fuel pressure test gauge to the Schrader port located just behind the alternator.
Turn the ignition switch on & start the engine. Observe the pressure: you should see 38-41 PSI at idle.
Turn the ignition off; reconnect the vacuum line to the fuel pressure regulator. Then disconnect the fuel pressure test gauge. Watch out for squirting gas when you do this.

Fuel pump pressure test
Disconnect the larger of the two fuel lines up by the Schrader valve. It is the return line and does not have the Schrader valve on it. Find a piece of rubber fuel hose and clamp it on the return line coming from the regulator. Stick a bolt in the other end of the hose and make sure that all your connections are tight and leak proof as possible. When this powers up, you don't want fuel squirting everywhere. Hook up the fuel pressure test gauge. Turn the ignition switch on and watch for leaks. You may want to use a helper inside the car to cut the switch off quickly if you have a leak. To trick the fuel pump into running, find the ECC test connector and jump the connector in the Upper RH corner to ground.

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Caution!!! You have blocked the return line for the fuel pump! Pressure will rise very quickly past safe levels with a good pump
If the pressure goes up past 55 PSI, the pump is good and the fuel pressure regulator is bad. If the fuel pressure does not hit 55 PSI or more in a few seconds, the pump is bad or you have electrical problems.
 
Do you have your pressure regulator cranked all the way up (if it is adjustable)? I've recently had the rubber line connecting the pump motor to the pump housing outlet (assembly inside the tank) split down the middle, so only about half the fuel was making it to the rails.
 
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