Thread: Breaking Down - Fuel System

The trouble with mystery problems is .... If the motor works ... theres no problems ... So it is hard to find and you can only check everything

SO .... Do the usual maintenance checks ... clean or replace the relief valves / sensors on the EFI fuel rail .... Pull & check all the relay wires & check or add some extra earth wires from the body & motor to battery



Something you can do ...

Go buy some "Airostart" or "Circuit board cleaner" spray can & also a 2 litre bottle of water

Leave them in the car

Next time it breaks down .... The mystery problem arises .... Do the following

1: Open the bottle and pour water on the Amplifier on the side of Dizzy to cool it down ... IF it starts ... Then you have a stuffed Amp ... and at least you know the fuel system is OK

IF that don't work

2: Spray the "Circuit board cleaner" down the manifold and give it a go ... IF it starts ... at least you know it is fuel and nothing else

Hope it helps

Mike

Thanks Mike,

I actually just read this on an old topic:

THis is going to sound wierd. But occasionally, if the pressure drops...temp drops overnight etc.
I get something similar. Car, fires up then dies. I get out, open the gas cap, hear a hiss...like vacuum release...then get back in, give the pump a second with the key on to get fuel pressure and it fires right up as normal. It may be that the gas cap I have has too much seal. I don't know - but apparently during the last emissions check my old one failed, and I bought one on the spot from the mechanic that tested it (10 bucks).
Similarly if I have driven all day out in the desert heat, then let it sit for a couple of hours, as its cooling in the evening, then try again I have the same issue.

So if you have replaced it at some point, that might be the culprit....if nothing else its worth a check.
Ed

Sounds like it could be my problem? Will take the car back and also try this out if it breaks down on me again.

Originally Posted by westonben

Thanks Mike,

I actually just read this on an old topic:

Blocked fuel tank breather line

Sounds like it could be my problem? Will take the car back and also try this out if it breaks down on me again.

Makes sense to me .... I guess the giveaway is to go for a half hour drive and then take the cap off the fuel tank straight away .... to listen for air being sucked back into the tank


Driving my boat a couple of times and forgetting to undo the air bleed on the fuel tank and the motor conks out

Hope it's simple as that ..... other than that it will be case of for a bit



Mike

Originally Posted by westonben

I've got problems.....

I've had the car break down on me twice in the last 3 weeks. First time it wouldn't restart after turning off the engine for a 5 minute stop.

Secondly, I was just coming down off the dunes (after a pretty bouncy time) and after 5minutes idling it died and wouldn't restart.

First time was definately no fuel getting to the engine, apparently the problem was a "wire". Language problems blocked any clearer details. I was stuck in the middle of nowhere so had to take it to a local garage.

Second time I got it towed to Land Rover. After 3 days they took a look at it and apparently it's working now and they can't find a problem.

I'm so fed up with the car and the garages here I'm thinking of selling. I don't want to, but I don't know what else to do...

Any ideas.... could the fuel relay be acting up? Can the inertia switch be temperamental?


For info, it's had a new fuel pump 3000km ago, new fuel filter at the same time.

Thoughts greatly appreciated.



1999 Discovery Series 1 3.9 V8 Auto Gulf Spec - Non Cat. Lucas Hot-Wire (Non GEMS)

Hi Ben,

I've had the fuel pump connector plug melt in these before now, the plug that fits onto the fuel pump unit under the floor in the cargo area has stupidly small pins, the resistance can be high enough to cause enough heat to melt the plug and the pins can have enough volt drop to cause the pump to stop. After cooling down and the resistance drops, full voltage will return and the pump will run OK again.

JC

I had the same problem about 2 months ago and never found the reason. All i know is that there was no fuel to injectors so i bypassed the wire from under injector to a direct +pos connection and she started, it wasnt the injector pump so must have been a relay somewhere but never really found which one it was for sure (just tapped and sprayed wd40 on all of em) it hasnt troubled me for 2 months now but i still carry the spare wire- may even run a switch to it one day as i had to get out of the car and disconnect wire to stop the trusty defender. i sort of heard that theres a relay sort of thing in battery compartment and near fuel tank, also it first happened after a very rough 4wd session. Hope this helps and if you ever find out what causes it let me know

Well I got it back from the dealer and they couldn't find a problem. Fired up for them and worked fine for a 60km test drive with pressue guage attached.

Will have to wait for the next breakdown. Will test the fuel cap trick shortly.....

Thanks for the ideas

Well I just took it for a drive and stopped, released the fuel cap and there was a very audible sucking of air. Sounds lie this might be it. Will investigate the breather and report back.

I guess I would have noticed this before if we didn't have pump attendants here!