So i replaced the injectors on the weekend on my mechanics advice. Car still seems to cut out soon after starting! (starts easy on both petrol and gas) so i decided to pull the fuel pump.

The new one i have is different to the old one(after being assured its the correct one) is it wrong or just an upgraded pump?

when i turned the accessories on there was no sound at all from the pump. when i started her and accelerated fuel came out fine. Do fuel pumps die a slow death and gradually lose strength (enough to justify the car cutting out) or do the just stop all together?

regards Tom

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The pump to the right of your picture is an external mount pump and is entirely un-necessary for a LR V8. Get the Bosch BFP772 pump or equivalent to suit VN-onwards 6 cylinder cars.

Pumps do work intermittently when old, its the brushes that wear out and lose contact, and the pump may also lose pressure due to wear in the pump itself.

in commodores the pumps tend to work till they give up, normally with no warning.
a few make extra noise when dieing.

also check in the tank incase you have a broken return tank to the swirl pot if fitted.
swirl pot is a small case inside the tank were return fuel goes to and fuel pump picks up so when tank is low you do not keep cutting out as you drive

Thanks bee

i will add that to the ever growing list of items i have bought that are wrong for this nightmare.. i mean car

as there was no sound from the fuel pump when i turned the accessories on does that mean its priming function is knackered?

get someone to turn the ign on/off/on/off while youre under the car and give the tank a good thump, if still no primeing, then (never worked on a efi rangie so dont know if their accesable) get a test light on the pump power supply and get someone to turn the ign on, if the test light lights up then the pump is at fault, if not look els where.

you say its on gas? i take it runs fine on gas and thats why you narrowed it down to a fueling problem? id change the fuel filter befour the pump as the filter will be much cheaper and u may aswell do it regaurdless of changing the pump or not. pump failure and a blocked filter are hard to tell between.

cheers, andy

the fuel filter is new. yep i had my ear pretty much on the pump when i had it flicked over. could it be something to do with the fuel pressure regulator?

Do a fuel pressure gauge install It's an easy job.

'88 3.5 flapper airflow meter models have no fuel pump switching until engine is cranking, as the movement of the airflap in the airflow meter allows the switching contacts to touch and energises the fuel pump relay.

JC

I find that pumps don't always come on with the ignition, so a definitive test is to operate the starter for a moment, and listen for the pump running for about 1 second after the starter stops turning.

In lieu of a pressure test crack the inlet junction to the fuel rail after operating the starter and see if pressure is present. Normal safety precautions apply!