Ve ss fuel pump not re-priming

[Trevor loves holden.]

Best thing is plug it into a tech tool a proper one that reads live data, could be just a upgrade software needed or a correction.

 

[Alex.a]

Thanks for the replys guys, have a little extra info regarding the issue.

So if I put the key in, ignition on fuel pump primes and car will start.
Turn ignition of, then attempt to start and usual issues pops up... No pressure and few seconds of spluttering before it dies... If I turn it off and wait 15 seconds (roughly) I hear the fuel pump relay click.. Ignition back on and the pump primes and it will start.

What tells the fuel pump module to fire the pumps when the car is running?? Does it receive cranking signal or similar?

With hp tuners zero faults, tried a scan tool and also no faults... However have not tried a tech2 or gm scan tool.
Could it be a faulty Bcm? Changed pump relay and have checked all fuses..
Is it possible to bypass the factory pump wiring/module and put 12v straight to the pump?

Thanks again

 

[Alex.a]

Best thing is plug it into a tech tool a proper one that reads live data, could be just a upgrade software needed or a correction.

Yes this is my next port of call.. Just need to find someone with one that's not a golden dealer lol

 

[Trevor loves holden.]

Have you tried pushing the unlock button on fob before re-starting it again?

 

[Immortality]

The fuel rail should hold pressure when the engine shuts off so there is most likely a problem with a non return valve in the pump or the regulator has a problem (hence the suggestion to test fuel rail pressures).

Has the fuel pump been upgraded to suit the larger motor? Is it still the factory style dead head fuel rail system?

 

[krusing]

I am guessing it could be either the fuel control module, Fuel Pump or the wiring/connector to the fuel pump its self,
After my experience with fuel pumps earlier this year, could either/or, as its a little wierd it start first go when the pump is cold and when the system has had a rest/sleep.

 

[Alex.a]

Std fuel system, pump was the next on the agenda to replace and injectors duty cycle is also up there.

The rails seem to hold pressure fine, the pump just won't re start after the initial engine start.
And it does this like clock work. After I have run the motor, I can depress the little gauge port on the fuel rail and there is a massive amount of pressure in the rails( I guess this is what the motor is spluttering and running on while there is no pump power) I did discover that if I unplug and then reconnect the the large loom connector in the engine bay, next to the fuse box (believe it runs back in the cabin to the bcm) the pump will immediately reprime and the car will start and run.

Can anyone tell me what give signal to the pumps to start when the engine is running? I'm confused as to why the the car will run everytime after the pumps have primed, yet another immediate start.. Nothing...

I have ordered a little pressure gauge for the rails to check the actual pressures.. Should be here Friday.

Also we can see via hp tuners that when the car is spluttering and trying to run that the fuel pump control module is receiving full voltage...

 

[Alex.a]

I am guessing it could be either the fuel control module, Fuel Pump or the wiring/connector to the fuel pump its self,
After my experience with fuel pumps earlier this year, could either/or, as its a little wierd it start first go when the pump is cold and when the system has had a rest/sleep.

Yeah my thoughts exactly.. I first thought pump but for it to fire up and run fine after its preset timed out period leads me to think it's something else.

 

[Trevor loves holden.]

Not a sticky relay is it?

 

[Alex.a]

Not a sticky relay is it?

Tried swapping relays, no change... Bit of a head scratcher