3.5 ltr V8 fuel pump trouble (91 Disco)

Hi all,

Hope someone can help this guy getting his Disco running again (never mind about all the rest its now becoming a complete restoration project)

So, recently I am having trouble with my fuel pump. It went from intermittent-not running to not-at-all now. The pump is fine. It runs when hot wired from the battery. Neither the relay is a problem. I fitted a new one and it clicks fine when turning the ignition switch. (that was through an other thread) Neither the inertia switch is the problem. That works fine and tested ok. And an immobiliser, I don't think its on it. Yes it has a fob and central locking/alarm but no immobiliser I think. The manual actually does not mention about an alarm or immobiliser at all.

That's where I am now, not knowing what to check next.

Maybe someone can explain the fuel pump wiring so I can check it. Cause there are 5 wires coming from the relay, but only 3 ending up at the pump. Prob 1 to the inertia switch but what about the other one ? (immobiliser and if so how do i know ?)

Other wise any hints are helpful. :clap2:


Regards,

Michael

Well, I assume there is no power to the pump?

And I havent got my Haynes handy but the diagrams in the back of there are very clear and helpful.

Remember ECU switches fuel pump relay.

Cheers.

Gee Noisy, you're right. Page 13-50. I have been looking at the starting system diagram and in the index @ fuel pump/system.

Think I'll have a close look at the ECU tomorrow

Thanks.

See you got the same machine. Yours in tiptop condition ?

Reg,

Mike

FlyingDutchman said:

See you got the same machine. Yours in tiptop condition ?

Reg,

Mike

Click to expand...

Hi mate

Yeah it's good thanks, great in fact tbh. It often throws a wobbler but the engine at least has never seriously let me down. Have had troubles but they've been simple enough, just hours and hours of head scratching til you get the bingo moment, but now it's a reliable and fun beast to run if I'm honest.

Good luck with it

Thanks,

Its raining here today and I am working later in the week, so let you know next week how I got on.

Reg,

M

Had 2 hours good weather and could not resist movin on. Took the ECU out, all looked good, inside and outside. After a break I connected it again, put the battery negative back on, and , the pump started.

The excitement was shortly lived as it died again soon. And dead it still is.

:doh:

Around 18 months ago my pump magically stopped working, took it out, stripped and Estes and rebuilt, hasnt packed up yet!

Keep Calm and Carry On !

Thanks.

A month later and I got it sorted now.

To clarify we are talking about a V8 injection here, which I assumed was standard, but appearantly it is not. And because it would sometimes run, I wanted to analyse it before starting to take everything apart.

Well finally I heard a relay clicking when it would cut out again. It turned out to be the main relay which controls the injectors AND the fuel pump that was faulty.


This to close this thread with a solution for future searches.


Regards,


Mike