if it were a jeep i'd have it fixed by now, this is my wife's 2001 blazer, 4.3 auto 4dr.

here's the issue, if it sits for more than 3-4 hours when i/she go to start it, the thing cranks for what i would consider a long time (10-15 sec). I am thinking fuel pump is allowing pressure to drain back into the tank, but throwing parts at a car that start at $350 is not an option i like or can redilly deal with. going out now to put a pressure guage on it since it's sat all night and see what happens. will post results as soon as i have them but any suggestions in the meantime would be very much appreciated.

 

Everything starts with a pressure check. Specifically check the pressure bleed down after the key is turned off. Also, have a look in the DIY section for the 96+ Fuel System Diagnosis thread. This will help you narrow down whether it is a faulty check valve in the pump or a leak in the system some place else (injector, FPR, or lines).

 

ok, fuel pressure was at zero before cycling the ignition, there are no leaks in the system that i can find, this is telling me the check valve in the fuel pump? so that means pump replacement?

 

PRESSURE GUAGE FOUND. pressure jumps right to 60psi with ignition first on, then dropps to zero within 1 min.....

 

That is the classic sign of a FPR leak, not a fuel pump check valve problem. You can verify that the pump is not the culprit by purchasing the required fittings to adapt the fuel line at the filter to at of the pressure gauge and turning the key on, then off. If the fuel pressure holds after the pump shuts off, then the problem is not in the pump.

The newer SCFI FPRs do not typically fail like the older units, instead they do not hold pressure over time, allowing fuel to constantly bypass back to the tank. This can sometimes lead to a lean condition at higher RPM with load.

The only real way to test the FPR is by disconnecting the return line at the back of the intake and plugging it off on the side that leads back to the engine. This will effectively dead-head the return line. If the fuel pressure does not decrease at that point, then the FPR is bad. If it still bleeds off, then you are looking at a failed o-ring in the injector pack of a failed injector and associated poppet nozzle.

 

what is the FPR?

 

wait, that's the regulator, only $40 compared to $240 for the pump, but i looked all over and could not find. is it under the black box behind the throttle body?

 

It is under the plastic intake plenum, inside the intake.

 

Hey Kyle-if you get this...I know that you want no PM's so here I go....By taking a pressure reading at the fuel filter-doesn't that not really rule out anything UNLESS you(and I think you can) simultaneously(with a partner) key it on and at the right moment clamp off the fuel line as the pump quits(after the 2 second prime)-line going to engine near transfer case that is rubber. Wouldn't doing it this way rule out(or not) the pump or an issue under the hood? Jerry PS or even pressure test at the under hood hook up and after the pump 2 second prime clamp off the feed line and if no bleed off, then release the clamp assby on the feed line. At this point if it bled off(you could double check) you're looking at a tank(pump) issue? Understand my Dinosaur philosophy?

 

No, the point of checking at the filter connection from the pump is to test the pump only, removing the rest of the system from the equation. You are not just tapping into the system, you are disconnecting it and putting only the gauge back onto that line, leaving the line that runs up to the engine disconnected.