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Returned the old fuel pressure tester and bought my self a new one at the local HF
The damn rental lies
KOEO- 20 psi
Rises to 31 psi while cranking then falls back to 20 psi
The more I turn the key without starting it builds pressure up to 40 psi and then drops back to 20-30 during/ after cranking
So then I should look to replace the FPR
I mean I only changed the fuel pump because I thought it had a bad check value but with the amount the FPR is letting out there's no way any pressure can build
A 1990 2.9 just has the single in tank pump.The FPR allows about 40 PSI into the fuel rail and rest of the fuel just returns to the tank.
You've replaced the fuel pump so thats not where the leak is.
If the rubber diaphram in the FPR is torn it will leak fuel into the intake. Remove the vacuum hose from the FPR, if it's wet theres the problem
If thats OK there could be a leaking injector.
I hooked a fuel hose from the regulator where the return line connects to the pressure tester and got about 50 psi in the first turn.
I know the regulator is supposed to allow some fuel back but it should allow 50 through and leave 20 in the fuel rail
I went a head and replaced my FPR but no good. The truck sounds like it wants to start really bad now, where as it wold just crank before, but doesn't have the push. The fuel pressure at rail was 35 throughout!
I hooked a fuel hose from the regulator where the return line connects to the pressure tester and got about 50 psi in the first turn.
I know the regulator is supposed to allow some fuel back but it should allow 50 through and leave 20 in the fuel rail
You have a bad understanding of how the fuel pressure regulator works. By blocking the return line with your gauge, you stop the regulator from working.
The regulator works by diverting excess fuel through the return line. It doesn't divert "pressure" into the return line, it diverts flow. When you blocked the return line with your gauge, you effectively dead-headed the fuel pump.
Have you tried replacing the ECT sensor? A bad ECT sensor will make cold starting the engine very difficult. Make sure you replace the right one, there are two. The one with 1 wire controls the gauge, the one with two wires goes to the computer.
what is an ECT and where would I find it? The truck won't start even after its been warmed up.
I was told there was the possibility a bad map sensor or the Air temp sensor in the intake could be my culprit.
Does anyone know the resistances of the sensors?