The last time my car was driven, it started stumbling like it was starved for fuel right before I got home. The tank was pretty low, but still just above empty. After turning it off, I tried to start it back up, only to hear it crank but not start. I immediately hooked up a fuel pressure gauge that showed ~18 psi. I tried to crank again to see what happened to the pressure while cranking. It started this time, but while maintaining the very low 18 psi and died as soon as I tried to open the throttle.

I then proceeded to send 12 V to the fuel pump prime connector to see how the pump responded. There was no change in fuel pressure. I then got someone else to apply voltage while I listened to the pump. I can hear it whirring, though fuel pressure at the Schrader valve does not change.

It does not appear that there is any bleed off in pressure, as the ~18 psi remains constant. I even opened my adjustable regulator all the way just in case it had SOMEHOW been turned down w/o my knowing and repeated the above check steps.

My battery shows that it has sufficient voltage (12.57 V) and all wiring at my relay also seems fine (11.46 all the way around).

I am making the novice estimate that there is a problem w/ my pump, though I am not really sure how failure typically occurs. In my case, IF there is failure, it is only partial as it still is making noise and consistently sending 15-20 psi to the rail.

BTW, I replaced a minimally clogged filter ~8 months ago and installed a new regulator ~2.5 months ago.

Sorry for the relatively long & newbie-ish post, but I cannot find any other examples of anyone w/ enough constants to compare to.

PLEASE let me know what you think or direct me to a source that should help me out.

Thanks in advance

 

These cars have a gas tank that is sort of V shaped, so when the gauge reads low level, it realy is low. Have you put some fuel for testing, or did you assume it had enough in the tank. It's distructive to the fuel pump to run dry.

 

Sorry, I forgot to mention, I did add a few gallons after I got home before I hooked up a gauge. The amount that was in the tank (even though it was pretty low) should have been enough to start it, but I just wanted to be sure.

If the pump still whirrs and is capable of delivering 15-20 psi, would this rule out a faulty pump? I am quite ignorant as to how this unit operates and would appreciate it if anyone can provide some clarity.

Thanks for the post

 

Its either:

-dieing pump - yes a pump can slow down, but not completely die.
-faulty AFPR (what brand is yours?)
-plugged fuel filter
-pinched supply line

You've got to rule those out, one at a time. You can test the FPR by blocking off the return line. If the pressure goes up as you restrict the return its a faulty FPR. Did you check the vacuum line to the FPR for fuel, which would indicate a broken diaphragm?

 

I will try the return line and vacuum line tonight once I get home from work.

As far as blocking the return line, has anyone had trouble pinching the line or are shutoff adapters worth the investment?

I believe that my AFPR is Hypertech. Has anybody heard anything bad about these?

Thanks for the help and methodical approach.

 

Did a search on this topic and saw this thread. Did it turn out to be a bad fump? I am experiencing the same thing.

Thanks!
Ken

 

When these suckers run out of fuel---they run out of fuel. If you sucked it dry and put fuel in and were not on a level surface, you may not be getting at the fuel.

I'd make certain that you have plenty of fuel before I considered any other problem.JMHO