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VN exec Need help diagnosing fuel issue

Vnshed

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89 vn exec. Vs berlina. 99 forester Turbo
I Bought a series 1 vn exec thats been sitting in a half open shed since 2006! 220xxx bit of rust around the rear screen but otherwise pretty clean. Ofcourse the fuel in the tank was ancient and smelled like off paint.

So far i have
Removed fuel tank,
Drained contents into a bottle
Flushed thoroughly with hot water, allowed to dry and chucked a litre if metho in the tank while it was out to vapourise any water left.

Replaced fuel pump with fuelmiser
replaced pump cradle
Replaced all necessary hoses, fuel filter, tank vapour hoses etc.
Replace oil pressure switch
Checked fuses, relay clicks on for 3 seconds as it should.
Fuel pump primed before it was pulled apart and cleaned etc.
Ive even connected another pump to the plug under the car near the tank. No noise. Not even a second.
Not sure where to go from Here apart from checking wiring/ earths. If the relays clicking on and off, is there air in the system stopping the pump priming?
Any help appreciated
 

MikeC

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Are you getting 12V at the pump plug with the ignition on?
 

BlackVXGTS

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Presumably you put some new petrol in the tank (you didn't say)? Try squirting some "Start You Bastard" into the throttle body and see if it starts. That will confirm if the problem is with the fuel system or something else.
 

Vnshed

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3 month late reply. Fuel tank was thoroughly cleaned and dried before refitting. Will be getting a volt meter and rechecking everything before i go any further. It ended up being put on the back burner due to other commitments but atleast the cars undercover. Have another s1 vn there that i can raid for parts. Should be good when its running
 

Vin999

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3 month late reply. Fuel tank was thoroughly cleaned and dried before refitting. Will be getting a volt meter and rechecking everything before i go any further. It ended up being put on the back burner due to other commitments but atleast the cars undercover. Have another s1 vn there that i can raid for parts. Should be good when its running
I am not saying this is your issue, but the vn/vp from memory the fuel pump is tied into the oil pressure wiring scheme and can stop at start from ecu if there is an issue with this engine safety bit, so maybe have a look at wiring details/diagrams for the car, incase there is something going on ????
 

gtrboyy

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Jam some aerostart down it's gullet...if it starts/runs a bit it's fuel issue.

Then check for fuel pressure....maybe get someone to crank while you belt fuel tank could also check wiring with test light or try hotwire f/pump.

Could be wrong but think vn/p will run with oil pressure switch disconnected whereas vr/s won't..wiring differences iirc.

Fairly sure all models will do the prime f/pump a few secs then turn off
 

MikeC

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On a VQ 5 litre you can test the fuel pump circuits by jumping the pink and violet wires on the ALDL test connector. Apply 12V to these and if the pump runs its electrical circuits are OK. This engine should still run with the oil pressure switch disconnected.
 

losh1971

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Could be wrong but think vn/p will run with oil pressure switch disconnected whereas vr/s won't..wiring differences iirc.
Pretty sure my VR runs with oil pressure switch disconnected. I had to leave it off before to dry it out. Throws up a red light when its wet inside. Still runs fine with red light too. Maybe it changed with VS?
 

gtrboyy

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iirc wiring changes vn/p goes straight to relay while vr/s through engine harness to ecu or bcm...more to do with f/pump running is my guess.

can hotwire f/pump by bridging pins under dash (white plug?) on vn/p
 
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