FUEL PUMP/NOT PRIMING,

[superwedge]

hi all, car used to start on first turn, the fuel pump would prime for about 3 seconds when you turn the key and stop, but now it does not do this any more, so it has to turn other for a good 60 seconds before fires up slowly,any ldeas would be great ?

[adam quantrill]

I am guessing this is a V8 (from your other posts) but is it a flapper or hotwire air meter?

I only have experience with flappers and this is what I now do:

- Turn over for 2 seconds max
- Leave ignition on
- Wait 5-10 seconds
- Start and it will fire on the button.

This saves cranking for 10's of seconds at a time with consequent strain on the starter and battery.

[superwedge]

hi adam, yes its flapper , don't why its not priming any more like it used too,that way the pressure was there in the rails,

[mrzigazaga]

Hi Dave


Remove the air intake pipe from the plenum and then put ignition on position 1 ...then gently push the flap on the AFM...you should hear a small squeak..this will be the fuel pump priming...replace pipe and start.

[wedgewood]

Some things to check based on starting problems that I have had. Firstly check that all your fuel pipes are secure and that none are weeping or leaking. That your fuel pump is not blocked and finally that the multi plug connector is pushed firmly home on the ecu.

[wedgewood]

sorry that should have read fuel filter... Also worth checking that the pump is getting enough power, check that the battery and wiring to the pump is good. Is the fuel pump relay pushed firmly home?
Is this problem from hot or cold or both? If its from hot it may be a vapourization issue due to the recent hot weather coupled with heat soak from the engine the fuel may be boiling in the rail.

apologies for all the random ideas but hopefully it will help.

[superwedge]

hi al,no its from cold,start great from hot, I try what zig says, maybe that get the priming the pump to the nom??????/

[adam quantrill]

To be hones what is happening now is how it's supposed to work. I guess it''s a safety feature so if the engine stops the pump stops running. Maybe before you had a fault where the flap wasn't closing fully?

With my method the first turn-over gulps some air through the AFM which runs the pump for a couple of seconds, and the delay lets the fuel rail pressurise a bit up to the top, collapsing any vapour bubbles, and any fuel that made it past the injectors in phase 1 sits there in the intake vapourising. It seems to work for me, anyway.

[mrzigazaga]

adam quantrill said:

Maybe before you had a fault where the flap wasn't closing fully?

Good point...the flap spring does become weak over time... have you checked your emissions to see if its running lean or rich...mine gradually over a period of a year became very lean...however she still starts bad now that has been rectified...

So the cigarette lighter socket plug to the Cold Start Injector works for me...I even need it in the weather we are having now...Once she is up and running she is pulling like a train and never hunts or misses...happy days...