What should fuel pressure be if fuel pump is not activating?
If the fuel pump relay IS NOT activating the fuel pump, the fuel pressure test gauge will register 0 PSI when cranking the engine. If the fuel pump relay is activating the fuel pump, then it’ll register about 56-62 PSI even if the engine does not start. Any fuel pressure below 50 PSI and the engine will NOT start.
How to test a GM 4.3L fuel pump?
More GM 4.3L, 5.0L, and 5.7L Tutorials. It’s very important that you start off your fuel pump relay diagnostic by first testing the fuel pump pressure with a fuel pressure test gauge. If the fuel pump relay IS NOT activating the fuel pump, the fuel pressure test gauge will register 0 PSI when cranking the engine.
What should fuel pressure be on GM 4.3L Vortec?
You can find this tutorial in Spanish here: Cómo Probar La Bomba de Combustible (GM 4.3L, 5.0L, 5.7L) (at: autotecnico-online.com ). The fuel system in your 4.3L, 5.0L, or 5.7L Vortec engine needs at least 50 PSI of fuel pressure to start.
What happens when fuel pressure is below 50 psi?
If you do see any fuel pressure below 50 PSI, the fuel pump although working, is not creating enough pressure to start the engine and is defective. Testing the fuel pump’s pressure with a fuel pressure gauge will help you avoid replacing good parts and/or getting the wrong diagnostic test result.
You can find this tutorial in Spanish here: Cómo Probar La Bomba de Combustible (GM 4.3L, 5.0L, 5.7L) (at: autotecnico-online.com ). The fuel system in your 4.3L, 5.0L, or 5.7L Vortec engine needs at least 50 PSI of fuel pressure to start.
How to check for fuel leaks in a GM 4.3L?
Once the fuel pressure gauge registers pressure, check for fuel leaks around the Schrader valve. It’s very important that NO fuel leaks are present for the accuracy of the test. Once you have verified no fuel leaks, continue to the next step. Have your assistant crank the engine as you eyeball the fuel pressure gauge.
Can a GMC fuel pressure regulator go bad?
Then it will start. It runs/drives fine. I had a 98 Camaro RS with the 3.8 V6, and it had very similar symptoms (fuel pressure regulator was bad/going bad), but I was just wanting to make sure. Also, if I’m not mistaken the FPR is internal on my GMC, Right?
Can you test the fuel pump on a GM Truck?
And although GM did not include a Schrader valve to which you could connect a fuel pressure gauge, it can be tested with one to find out if the fuel pump is producing the correct pressure (or not).