Fuel pump problems...solved...but not sure why!!

[FARKIT]

Okay - replaced the yellow connector - made no difference.

Then powered the pump directly to check if it was okay.
Pump primed okay.

Reconnected the pump electrics, turned the key, pump primed again, and hey presto - she was running!

Good that she's running - but any ideas as to why I had to prime it?
Is there a sticky valve somewhere worth checking?

There was a good 1/4 tank of fuel. I'll be changing the fuel filter at the service, but there must be a reason - any ideas anyone?

[phillpot]

Dodgey connection ? on mine there is a two pin connector in the wiring between where it comes out the bodywork and the connections to the pump. anyone of those joins could be corroded causing your problem, messing around down there may have temporarily "cured" it ?

[FARKIT]

Did think that - but the pump connections were very clean with no corrosion - wondered if there's a pressure switch somewhere, and by manually priming, it's been reset?

[GreenV8S]

No, there's nothing like that in the system. It seems to me that your original problem was an electrical gremlin. In that case, it's liable to come back unless you have found and fixed it.

[DJ8226]

Faulty pump could it be a sign its going to fail.....??

[FARKIT]

Think you're right - it probably is likely to return - so I suppose the thing to do is carry on driving until it breaks properly?

Otherwise, where do you start (or not!).....

[FARKIT]

Just a thought - but can old fuel cause a problem?

[DJ8226]

Wouldn't of thought fuel would be the cause. Here is a thought...Is your pump noisy as when I bought my car the pump worked and never failed but it was really noisy to the point you could hear it with the engine running! I heard Wiz's (fellow S owner)running and realised mine was above normal in operation so changed it, it might of been ok who knows. Back to yours if and when it stops working get someone to operate the ignition and give it a tap with a screwdriver and see what happens, always used to work with sticking starters. If it starts whirring surer as eggs is eggs its a bad connection or the pump is jiggered. HTH

[Le TVR]

Intermittent supply to the fuel pump is often the fuel pump relay.

This is not just a relay. The case holds a PCB with an ignition detector circuit and a PCB mounted relay. The soldering is usually somewhere between 'suspect' and 'inadequate'. Normally you find hairline cracks in the soldering of the relay output pins to the PCB and this causes all sorts of intermittent faults.

Resoldering all the connections has cured every dodgy one I have found (unless they have been waterlogged and corroded).

[FARKIT]

That's a great help - I'll do that as soon as she's back from the body shop....