Fuel starvation

Hi
Disco 2 - 180k miles. I had a problem starting, with fuel pump making strange burbling noise. After starting it ran fine. Mechanic diagnosed 'knackered' pump which was replaced. Within a couple of weeks the starting problem returned - plus a new one, engine cutting out after 5 miles, and 2/3 minutes wait before the fuel pump kicked in and after constant cranking would restart.
Garage diagnosed 'duff fuel pump' (it was a 'compatible' pump) and recc LR fuel pump. This has been fitted - but hasn't cured the problem.
Some oil in the loom but mechanic says not sufficient to be a problem. He's also checked that all the pipes are on right, not kinked. He has checked fuel flow and that the ECM is sending out all the right signals
The car was running fine before the fuel pump was changed, so could something have been dislodged in fitting - or could a new pump put too much pressure on another (ageing) component Fuel regulator? Fuel Filter?

UPDATE... Monday 28 January -
Fuel injector seals have been changed and vehicle now appears OK. One was definitely showing signs of leakage and two more were 'possible'.
BUT it still baffles me WHY... there was no cutting out before pump was changed. Did the increased flow or pressure finish off already dodgy seals? My guys spoke to LR mechanics and other 4x4 specialists - all say 'no - they must have always been faulty' - but if so why did it not cut out or run rough until we changed the pump?.

BryanH said:

Hi
Disco 2 - 180k miles. I had a problem starting, with fuel pump making strange burbling noise. After starting it ran fine. Mechanic diagnosed 'knackered' pump which was replaced. Within a couple of weeks the starting problem returned - plus a new one, engine cutting out after 5 miles, and 2/3 minutes wait before the fuel pump kicked in and after constant cranking would restart.
Garage diagnosed 'duff fuel pump' (it was a 'compatible' pump) and recc LR fuel pump. This has been fitted - but hasn't cured the problem.
Some oil in the loom but mechanic says not sufficient to be a problem. He's also checked that all the pipes are on right, not kinked. He has checked fuel flow and that the ECM is sending out all the right signals
The car was running fine before the fuel pump was changed, so could something have been dislodged in fitting - or could a new pump put too much pressure on another (ageing) component Fuel regulator? Fuel Filter?
Suggestions please...

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Your garage appears to be using the well-known "diagnosis by replacement parts method" - they are not finding the real problem and you are paying for their incompetence.

There really is only one one to ensure the fuel pump and FPR are working correctly and that it to measure the fuel pressure going in and out of the FPR, using proper equipment.

Or carry on replacing bits until you come to the end of your cash and throw the car away in disgust.

This problem needs proper diagnosis before any more new parts are fitted - if this garage can't/won't do that, you should move on.

Don't guess, verify!


The very best of luck to you,

Dave

Injector o-rings & washers.....

thebiglad said:

....Don't guess, verify!......

Dave

Click to expand...

Bennehboy said:

Injector o-rings & washers.

Click to expand...

Check your oil level and it's smell. If it's rising and smells of diesel it's your injector seals and needs doing asap before it runs away to destruction.
Griff

as ben said but also check that airbleed valve on the fuel filter head first pipe on the left probably choked up with soot from blown injector seals and hence the burbling sound from pump

Thanks for your advice guys.
The garage have already checked fuel flow from the pump and have eliminated a blocked filter. The mechanic has checked the oil (and the ECM end of the injector loom) and says there is no diesel smell - and no rise in sump oil level - which suggests that injector seal leakage is not the most likely problem.
They have the kit to check FPR pressures and are doing that Friday and will take out the FPR to check for internal ridges etc which could cause it to stick.
What is confusing is that the cutting out only started AFTER the new fuel pump was fitted. Previously there was a noisy pump and a cold start problem which had got gradually worse over a couple of years. But once running it was fine, no cutting out, power loss or rough running.
Now it will start, warm up, tick over for up to an hour - but take it out onto the road (warmed up first or not) and within 5 miles it has cut out. Wait 3 or 4 minutes it will restart and run again for same sort of mileage. Incidentally in both directions from and back to the garage you go down hill then up again and the cutting out is always at the top of the hill.
Is it just coincidence that something else in the fuel delivery system has gone tits up since new pump was fitted or could fitting a new pump put pressure on the FPR for example and cause it to fail in some way?
Sorry about the long explanation but both Matt the mechanic and I would welcome any suggestions, since at Matt says it will save him time and therefore save me money.

did they have a look at the air bleed valve .
the coper injector washer wont fill sump with oil but will send the fuel back to tank full of air bubbles and soot the soot then chokes the bleed valve .
do you keep your tank full or under half mostly

I'll ask about the bleed valve. I usually keep the tank around half full.

The air bleed valve is a bit mucky - but not really sooted up. Having checked everything else - including fuel temperature, FGR etc and spoken to several LR specialists, they've come to the conclusion that its probably the copper injector seals. That's what they will be doing (at 90p each its not worth just checking them) on Monday.
Ching ching.... its a Land Rover thing!