Disco 4 (LR4) Disco 4 low fuel pressure

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Disco lad

New Member
Posts
8
Location
Ireland
HI all,
I had my 15 Disco 4 serviced last Wed. It was normal, no fuel filters etc however, and I paid and collected from the garage on wed evening. I did a lot of towing on Thursday. Whilst going home from work on Sat the engine just stopped in the middle of the road. It was turning and not firing. Today I got it to the garage who maintain that it has low fuel pressure. I can't help but feel that the issue is related to the last service, as this machine has been perfect in every way..any idea's lads?????
 
They run really low fuel pressure as normal, go to the disco3 forum and search for robbies guide to the low fuel pressure system.

Have you given the crank pulley a good wiggle with a bar?
 
Disco lad said:
HI all,
I had my 15 Disco 4 serviced last Wed. It was normal, no fuel filters etc however, and I paid and collected from the garage on wed evening. I did a lot of towing on Thursday. Whilst going home from work on Sat the engine just stopped in the middle of the road. It was turning and not firing. Today I got it to the garage who maintain that it has low fuel pressure. I can't help but feel that the issue is related to the last service, as this machine has been perfect in every way..any idea's lads?????
Click to expand...
If it's cranking over, and got no or really low high pressure fuel delivery, then I'd ask if the crank has failed, which is a distinct possibility.
 
Disco lad said:
Would this accurate, The fuel rail sensor is also only showing 3 volts - I'm told that the brain won't let it start unless it's reading at least 5??? May be a broken sensor????????

https://www.turnermechatronics.com/land-rover/discovery-3/discovery-3-4-non-start.html
Click to expand...

The PTM/ ECU will likely inhibit staring if the sensor isn't receiving a decent rail pressure. However you need to determine if its a faulty sensor (unlikely), or there is actually any fuel pressure in the rail.
Unfortunately the D4 is known to suffer crankshaft failure, which means the timing belts won't turn, which in turn stops the HP fuel pump from generating fuel pressure.
 
So that could be a timing chain, however we did spray some quick start into the breather and it started and ran smoothly enough until it had burned out the quickstart??
 
Disco lad said:
So that could be a timing chain, however we did spray some quick start into the breather and it started and ran smoothly enough until it had burned out the quickstart??
Click to expand...

If it ran on ether, then presumably the timing belt is turning, so that's good.

Really you need to get the live fuel pressure data from the ECU, as both low and high pressure figures are relevant.
 
Hi all, just an update on my fuel issue. The fuel pump broke down with steel shards going through the system.So far we have changed all fuel related parts, tank, injectors, fuel coolers, hi pressure pumps and all pipe works, totaling circa 5K.
Now the engine has a very irregular idle rev, the whole jeep is shaking, plus there is a serious whistle from the turbo area. We took the side off the turbo and it doesn't spin when the engine is ticking over. ..any idea where we went wrong??
 
Disco lad said:
Hi all, just an update on my fuel issue. The fuel pump broke down with steel shards going through the system.So far we have changed all fuel related parts, tank, injectors, fuel coolers, hi pressure pumps and all pipe works, totaling circa 5K.
Now the engine has a very irregular idle rev, the whole jeep is shaking, plus there is a serious whistle from the turbo area. We took the side off the turbo and it doesn't spin when the engine is ticking over. ..any idea where we went wrong??
Click to expand...
Calling it a "Jeep"!
May have upset it!;)
5K? FFS, you can buy 2 TD5s for that!
As a result of a broken fuel pump?????:eek:
I am still staggering around the room looking for a comfortable place to pass out!:(:(:(:eek:
 
Well then perhaps you have Covid
There were metal shavings in the fuel filter so all pipework, injectors and fuel tank had to be replaced or sonically cleaned. Would you risk a half job and then having to do it all again, never the day of labour just to lift the body up. Get real my friend, have you priced injectors lately....ffs
 
Disco lad said:
Well then perhaps you have Covid
There were metal shavings in the fuel filter so all pipework, injectors and fuel tank had to be replaced or sonically cleaned. Would you risk a half job and then having to do it all again, never the day of labour just to lift the body up. Get real my friend, have you priced injectors lately....ffs
Click to expand...
Mate you have all my sympathy!!
I just cannot believe that the particles got so small they got through the filter, any pics of these, i.e. what was found when doing all this cleaning?
I never do half a job so no I wouldn't risk it.
I am real, I do know the price of injectors, etc I also know the price of labour if you don't do the job yourself!
Just too old skool to understand how the breakdown of a relatively simple part can cause all this mayhem.
Any nearer finding what it wrong with it now?
Do hope you get it running properly again soon.:)
 
Stanleysteamer said:
Mate you have all my sympathy!!
I just cannot believe that the particles got so small they got through the filter, any pics of these, i.e. what was found when doing all this cleaning?
I never do half a job so no I wouldn't risk it.
I am real, I do know the price of injectors, etc I also know the price of labour if you don't do the job yourself!
Just too old skool to understand how the breakdown of a relatively simple part can cause all this mayhem.
Any nearer finding what it wrong with it now?
Do hope you get it running properly again soon.:)
Click to expand...


Where I used to work the van guys were always doing misfuels, (99 percent council vehicles and 99 percent of them were female!) and it was exactly as Disco lad posted, new everything, in the end they did manage to get it down to just pump and inj recon, the rest was steam cleaned out.

Common rail is great, until it goes wrong!
 
Disco lad said:
Hi all, just an update on my fuel issue. The fuel pump broke down with steel shards going through the system.So far we have changed all fuel related parts, tank, injectors, fuel coolers, hi pressure pumps and all pipe works, totaling circa 5K.
Now the engine has a very irregular idle rev, the whole jeep is shaking, plus there is a serious whistle from the turbo area. We took the side off the turbo and it doesn't spin when the engine is ticking over. ..any idea where we went wrong??
Click to expand...


Maybe try one of the cheap laser temperature gauges off of ebay, and see which cylinder has a different /lower emperature to the rest, then at least you know where to concentrate your efforts.

Iirc the 3.0 has two turbos, and one is controlled by a valve, so bascially does not work until needed, i think it is a bit smarter then that and does get a pulse to spin it up every few seconds/minutes?

Sounds mad, but have you given the front crank damper a little pry with a lever bar? engine off obviosuly!

Best of luck
 
lynall said:
Where I used to work the van guys were always doing misfuels, (99 percent council vehicles and 99 percent of them were female!) and it was exactly as Disco lad posted, new everything, in the end they did manage to get it down to just pump and inj recon, the rest was steam cleaned out.

Common rail is great, until it goes wrong!
Click to expand...
Mad!
 
lynall said:
The trucks are the same, you even have to change the fuel filters in a certain way to stop any debris getting into the clean side of the filter housing.
Click to expand...
I can understand about total cleanliness when changing fuel filters. The injectors do not need anything at all in the way of foreign objects going through them.
But I still fail to see how the filter didn't block the swarf from the "blown up" fuel pump. Did it really rip towards it at such speed to rip through it? And if so, where did the force come from to drive it there?
Looks as if some kind of fail safe thing ought to have been incorporated in the pump, like a skinny part of the drive shaft designed to fail first in the case of a sudden blockage rather than passing the damage on.
And this is progress?
Blown fuel pump means you have to take the body off! Imagine telling that to a mechanic back in the 70s!
 
Yeah, thats it. After 4 landcruisers the disco 4 was a revolution in terms of comfort, power, gear box and excellent with my 14' trailer but it takes a days labour just to get at the engine to do any work. By all accounts the new defender is worse. Real shame
 
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