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Help Wanted: fuel pump wont prime.
Posted:
Tue Aug 11, 2015 9:45 pmby chubbs
Hey all.
Having an issue. My fuel pump will not prime. The car was left in the garage for a week while i was in hospital and when i came back the battery died. So i jump started it and all was good. Next morning i went to start it again and it would crank but not start up. I notice my pump was not priming and i had no fuel pressure.
What i have done:
Checked all the fuses and replaced
Checked and replaced main relay and fuel pump relay
Checked all the wiring lumes from relays to fuel pump for power and grounds all was good
Replaced fuel pump controller
Replaced fuel pump
Even replaced ecu thinking it may have cooked the ecu jump starting the car.
The fuel pump will not prime and i am out of solutions.
Any ideas?
Re: Help Wanted: fuel pump wont prime.
Posted:
Tue Aug 11, 2015 10:30 pmby THE SpecB
chubbs wrote:Hey all.
Having an issue. My fuel pump will not prime. The car was left in the garage for a week while i was in hospital and when i came back the battery died. So i jump started it and all was good. Next morning i went to start it again and it would crank but not start up. I notice my pump was not priming and i had no fuel pressure.
What i have done:
Checked all the fuses and replaced
Checked and replaced main relay and fuel pump relay
Checked all the wiring lumes from relays to fuel pump for power and grounds all was good
Replaced fuel pump controller
Replaced fuel pump
Even replaced ecu thinking it may have cooked the ecu jump starting the car.
The fuel pump will not prime and i am out of solutions.
Can you read from diagnostics using tactrix or the like ?
Any ideas?
Re: Help Wanted: fuel pump wont prime.
Posted:
Tue Aug 11, 2015 10:31 pmby norbs
Is this for real? You changed all those parts? I suggest jacking up the number plates and installing a new car
Re: Help Wanted: fuel pump wont prime.
Posted:
Tue Aug 11, 2015 11:07 pmby dr20t
Sorry to hear.
Check Alternator connection and fusible link to alternator in your main fuse box in engine bay
Is the car cranking over (but just not allowing pump to run)?
If so, then check the earth to your fuel pump controller (its connected on the inner rear quarter panel)
If its not cranking then check your body control module. Infact check your body control module in any event.
The fuel pump circuit is linked to many circuits in the canbus setup from memory, including:
Starter circuit
Ecu test (when you switch acc on and needles sweep on the cluster)
Alternator (for overrun)
Failing that you may need to run an oscilloscope through the car to test for electrical shortages / leaks
Good luck mate and keep us updated
Mick
Re: Help Wanted: fuel pump wont prime.
Posted:
Wed Aug 12, 2015 2:17 amby chubbs
dr20t wrote:Sorry to hear.
Check Alternator connection and fusible link to alternator in your main fuse box in engine bay
Is the car cranking over (but just not allowing pump to run)?
If so, then check the earth to your fuel pump controller (its connected on the inner rear quarter panel)
If its not cranking then check your body control module. Infact check your body control module in any event.
The fuel pump circuit is linked to many circuits in the canbus setup from memory, including:
Starter circuit
Ecu test (when you switch acc on and needles sweep on the cluster)
Alternator (for overrun)
Failing that you may need to run an oscilloscope through the car to test for electrical shortages / leaks
Good luck mate and keep us updated
Mick
The car will crank over but wont let the pump run. I will keep diagnosing but im at the point npw where i shall take it to the dealer i think. It has me stumped.
Re: Help Wanted: fuel pump wont prime.
Posted:
Wed Aug 12, 2015 8:01 amby THE SpecB
If you can't back up what your doing take it to people that know.
Re: Help Wanted: fuel pump wont prime.
Posted:
Wed Aug 12, 2015 8:30 amby bigBADbenny
Have you tried applying direct 12v to the fuel pump (w/neg to the chassis) ?
Re: Help Wanted: fuel pump wont prime.
Posted:
Wed Aug 12, 2015 9:53 amby dr20t
bigBADbenny wrote:Have you tried applying direct 12v to the fuel pump (w/neg to the chassis) ?
Be careful with this as fuel pump controller regulates the voltage through variable earth
Re: Help Wanted: fuel pump wont prime.
Posted:
Wed Aug 12, 2015 12:50 pmby chubbs
dr20t wrote:bigBADbenny wrote:Have you tried applying direct 12v to the fuel pump (w/neg to the chassis) ?
Be careful with this as fuel pump controller regulates the voltage through variable earth
I think i may have found the problem. Possibly my alarm system. When i bought the car it had a vipe alarm already installed. It is hooked up to ignition cut and fuel cut. I will get this removed and hope it works
Re: Help Wanted: fuel pump wont prime.
Posted:
Wed Aug 12, 2015 3:49 pmby dr20t
That would definitely make sense
Good luck with it
Re: Help Wanted: fuel pump wont prime.
Posted:
Wed Aug 12, 2015 3:50 pmby dr20t
Best way to check is to test your fuel pump controller trigger wire to see if its getting a signal when key is in accessories position
Yellow wire from memory (or black with yellow). But don't take my word on this as its been a while. You can look up the workshop manual to check wiring diagram for the controller.
Re: Help Wanted: fuel pump wont prime.
Posted:
Wed Aug 12, 2015 4:25 pmby gtbsti
chubbs wrote:dr20t wrote:bigBADbenny wrote:Have you tried applying direct 12v to the fuel pump (w/neg to the chassis) ?
Be careful with this as fuel pump controller regulates the voltage through variable earth
I think i may have found the problem. Possibly my alarm system. When i bought the car it had a vipe alarm already installed. It is hooked up to ignition cut and fuel cut. I will get this removed and hope it works
I looked at your build thread and couldn't see if you had an immob or alarm so didn't mention it. Hope you fix it mate
Re: Help Wanted: fuel pump wont prime.
Posted:
Wed Aug 12, 2015 7:26 pmby bigBADbenny
Hope so too, 99% of all googleable Subaru fuel pump issues are related to the un-lamented Brandt alarm on earlier cars
Re: Help Wanted: fuel pump wont prime.
Posted:
Tue Aug 18, 2015 8:59 amby gtbsti
Fixed Alex?
Re: Help Wanted: fuel pump wont prime.
Posted:
Wed Aug 19, 2015 7:14 pmby chubbs
Havent touched it since as i am in europe for another 5 weeks. When i get back i will have a crack.