Omega Owners Forum
Omega Help Area => Omega General Help => Topic started by: ViaraiX on 23 February 2010, 12:43:40
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Recap... No fuel is getting to engine...
I have stripped down fuel pump, everything I've tested so far works independantly on its own, but as a whole I am still not getting any fuel...
Fuel pump was taken out completely, placed into a container of model fuel and hooked up to a 12v battery, pump worked fine.
Multimeter hooked upto the 12v feed to the pump, ignition turned and shows a constant feed (~10-11v)
Fuel pump reconnected and I connected a seperate piece of fuel line from output feed and placed into a container, turned ignition over, no fuel came out.
I am at a totall loss, there is obviously power getting to the fuel pump and fuel pump seems to work fine outside of the car.
Unfortunatly the other half is working late all week so havent been able to get a 2nd pair of hands so I cant check if I can hear pump while turning ignition (and my arms just arent long enough :(
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Have you done the paperclip test?
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papper clip just shows normal no rpm
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Were there any other symptons prior to this. IIRC signal from crank sensor also needed for fuel pump to deliver to rail
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Are you sure this isn't some other problem such that the ECU is not activating the fuel pump?
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pump is a 2 wire job, put voltage into pump and it spins, multimeter is showing voltage going to plug and I am assuming that any ECU / crank sensor control would not send the voltage through?
Its stripped right back atm, basically plug into fuel pump (showing voltage going to it) and a fuel line straight off the pump (to ensure any blockage or futher issues at rails is ruled out) into a container
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V6 needs a signal from crank sensor for fuel pump to run.
I know, I've been there ::)
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Were there any other symptons prior to this.
Not really, car wouldnt start a few times, but every time when it finally did start it ran like a train.
Never stalled whilst moving except for this final time (stalled whilst parking and never restarted)
I really dont think the crank sensor is the problem, trouble is as its such a common fault thats what all the garages are suggesting but as above if it was the crank sensor surely voltage would not goto pump as there are no other "signal" wires etc... to pump for it to be powered but not spin
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Not trying to be funny or anything, but is there enough fuel in the tank ?
HTH
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yeah, 1/4 tank and can see its sitting in plenty of fuel
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Could it be a blockage in the fuel supply? All your tests seem to be on power supply,and not fuel supply, sorry if this appears daft just a thought. Hope you get it sorted :y :y
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Just another thought check out the filter cartridge forward of diff
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fuel supply is fine... it sits in a puddle of fuel which it sucks up, can see it sitting in plenty of fuel.
dont even get to the 2nd fuel filter, have a seperate line coming straight off the pump for testing
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Sounds a lot like crank sensor mate
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V6 needs a signal from crank sensor for fuel pump to run.
I know, I've been there ::)
Agreed. I don't think it even fires up to prime the system until cranking is detected. If you're seeing power at the pump without cranking the engine (and 10-11v is suspiciously low) I smell a rat.
Remember that a multimeter has a very high impedance meaning it doesn't load the circuit under test. If you were testing for power with the fuel pump disconnected I couldn't mind betting there is nothing there once it's connected.
A good diagnostic step would be to remove the fuel pump relay and bridge the contact connectors (the two wider pins) using a short length of wire with a spade connector on each end.
If you now get fuel flow, pump and wiring is fine. If the engine starts and runs - suspect fuel pump relay. If engine doesn't now start despite the fuel pump running continuously - crank sensor.
Kevin
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Success!!!
Turns out to be a dodgy connection on the plug which connects to the metal plate.
Reconnected all the fuel lines and manually ran 2 wires to a battery booster and spun pump that way, fired up first time
plugged back in, still wouldnt fire
pierced a small hole in top of wire before plug and checked continuity between wire and pump ... nothing
bent pins a bit, jiggled wiring in plug ... got continuity
turned key ... started first time
trouble is not sure if it is the plug itself or the socket, both of which i will presume are awkward to source / replace and theres no easy way to replace with own connectors :(
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Agreed. I don't think it even fires up to prime the system until cranking is detected. If you're seeing power at the pump without cranking the engine (and 10-11v is suspiciously low) I smell a rat.
mis-wording on my part, the power was whilst cranking, not just with ignition on.
think it was 10-11v because the battery has been under some strain the last couple of days constantly cranking with no reward :(
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Agreed. I don't think it even fires up to prime the system until cranking is detected. If you're seeing power at the pump without cranking the engine (and 10-11v is suspiciously low) I smell a rat.
mis-wording on my part, the power was whilst cranking, not just with ignition on.
think it was 10-11v because the battery has been under some strain the last couple of days constantly cranking with no reward :(
Ahh, OK. It's quite normal for the voltage to drop a volt or two when cranking. :y
Glad it's sorted (or at least the fault has been located).
kevin