welshcossie

Hi guys

Been having a problem with the saff as it doesnt seem to be starting. I've tracked the problem to the fuel pump wiring but im a bit stuck so wondered if some1 could help me out. 1st thing, the fuel pump has previusly been rewired so there doesnt seem to be a inertia switch in the boot but there is a relay instead. I do still have a relay under the glovebox aswell is this right?i have traced the wires and have power from the battery to the relay in boot, but the wire that comes from the fuel pump doesnt have power, is this because of the relay in the glove box? I managed to briefly get it running yesterday but it died almost straight away and now doesnt start at all. I took the yellow relay out completly yesterday and couldnt hear the pump prime, but when i put it back in, I can hear the pump switch on briefly when i switch the ignition on. any help would be hugely appreciated as its really winding me up now!!!

delbee1

Do you have a test light??

I would check what +/- you have at the relay with ignition off and ignition on, maybe grounding out somewhere

The other thing to check is that pump works, you could unplug and put a + and - direct

delbee1

Also test what +/- you have at original relay

welshcossie

cheers mate, i havnt got a test light but will try and get one and check these things.

Psycho Warren

iTrader: (5)

multimeter helps loads on these things.

test the connectors at the relay holder for the permenant live to fuel pump and the ignition live that triggers the relay.

If good, bridge the connector to give power to the back of the car and check the new wiring to see if its getting through and if all works. if it does, probably new relay time.

If not just systematically work down the wiring.

Electrics need not be complicated. In simple electrical circuits on most older fords just think of wires as pipes carrying a flow of electrons very crude obviously but can be helpful to understand why things arent working as they should.

welshcossie

Thanks mate, i've had a multi meter to part of it and the constant live seems to be fine, so wondering if its the ignition live thats the problem. will take another look at it on weekend i think. i've had it running briefly so thinking it cant be anything to serious...hopefully!!

carl n 1977

alarm maybe

welshcossie

i havent thought bout that mate, i will look in to that also

martysmartie

iTrader: (1)

The fact you can hear the pump priming shows this is unlikely to be the problem!

What happens on a rewire is the original relay is used as a 'trigger' for the new one, so you do need that original relay, as it powers other components as well!

It's perfectly normal what you describe, as the pump only primes when the ignition is switched on.

I would check for 'ignition' is present next...

Martin

Stu @ M Developments

iTrader: (12)

Correct. I think your barking up the wrong tree here personally mate.

whizzisat114

iTrader: (2)

fuel pump will start to run as you crank it over aswell
check crank sensor and phase sensor wiring also double check ecu connector and relay