[Trickediatr]

Fuel pump does not prime car will not start, after TWEECER R/T installed. Took TWEECER off still no priming of pump and no start..please help

[SelmaAdam]

You must try trouble starting your car. The car will struggle to start and run because the pump cannot push enough gas through. A worn pump loses its pressure and the engine is being starved of gasoline.Consult the manufacturer or your trusted mechanic for fix.

[cgrey8]

Fuel pump does not prime car will not start, after TWEECER R/T installed. Took TWEECER off still no priming of pump and no start..please help

What's confusing here is that the normal problem people have is the fuel pump won't stop running. The default position for the fuel pump is to run. The EEC has to actively send a signal to the fuel pump relay to stop running the pump. As a result when the EEC is having problems executing a tune (e.g. no tune programmed in the tuning device or an invalid tune for the hardware in tuning device) the user will hear the fuel pump run and never turn off. That's one of the tell-tale signs there's a problem with the EEC and/or tuning device.

The description here suggests the fuel pump doesn't turn on, not that it doesn't turn off (the typical presentation when there are issues). So I'd start with verifying whether the fuel pump will run at all. Unplug the fuel pump relay and manually send 12v to the fuel pump via the fuel pump relay harness. If the fuel pump turns on when hot-wired, then the problem may simply be a bad fuel pump relay. If the fuel pump doesn't turn on yet you still see an electric spark when you insert the hot-wire to the pump, that would be an indication the fuel pump has seized.

...The car will struggle to start and run because the pump cannot push enough gas through. A worn pump loses its pressure and the engine is being starved of gasoline...

Aftermarket fuel pressure regulators are the most common source of fuel pressure bleed-down. Most stock FPRs for stock return-style fuel systems are capable of holding the pressure for long periods of time. My FPR will hold 40 PSI line pressure over night. However the aftermarket FPR I used to have installed would bleed the pressure down in a matter of about 2 seconds after the pump turned off. Once I upgraded to larger injectors and no longer needed to run a higher line pressure, I went back to a stock FPR.

However for those that do have the bleed-down problem and need more than the 1 second of fuel pump prime time, the GUFx strats do allow you to increase the number of seconds the fuel pump is primed when the ignition key is turned on. Just to test the feature, I set my tune to 5 seconds. And while my application no longer requires it, it doesn't bother me to have a longer prime time.

[TyraNoah]

You must try trouble starting your car. The car will struggle to start and run because the pump cannot push enough gas through. A worn pump loses its pressure and the engine is being starved of gasoline.Consult the manufacturer or your trusted mechanic for fix.

Quite Helpful.
Struggled with this for some times. Especially in the morning when the engine is cold. I actually tried changing batteries thinking its a jump start issue.

[RicksDL]

You must try trouble starting your car. The car will struggle to start and run because the pump cannot push enough gas through. A worn pump loses its pressure and the engine is being starved of gasoline.Consult the manufacturer or your trusted mechanic for fix.

Quite Helpful.
Struggled with this for some times. Especially in the morning when the engine is cold. I actually tried changing batteries thinking its a jump start issue.

Testing the voltage helps diagnose the issue.