Defender 90 TD5 Non start....

Yes, starts every turn of the key now.... I was just trying to work out why the fuel pressure was dropping to nothing, when it wouldnt start....

tilly2 said:

Yes, starts every turn of the key now.... I was just trying to work out why the fuel pressure was dropping to nothing, when it wouldnt start....

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It might be a problem on the pump's feed path which occurs when the voltage drops due to prolonged cranking, when it starts right away the alternator kicks in and the voltage is higher eventually replace the fuel pump relay with a new one and make sure the terminals are tight to rule this out but if this pressure drop happens again hook a multimeter to the pump's power supply at it's plug in situ and whatch the voltage while cranking

Easier said than done on a 90. Id have to drop the tank to get at the pump. I'll replace the relay, just incase, as winter is coming....

tilly2 said:

Easier said than done on a 90. Id have to drop the tank to get at the pump. I'll replace the relay, just incase, as winter is coming....

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Most people make a nice hatch in the back floor

tilly2 said:

Easier said than done on a 90. Id have to drop the tank to get at the pump. I'll replace the relay, just incase, as winter is coming....

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I thought there is a hole in the boot for that like on the D2... no probs, you can measure in C0378/0392 pin 4(white/purple wire) against earth cos from there it goes directly to the pump and pray to be good contact to power and earth in the pump's connector... eventually spray some contact cleaner in it

tom1979 said:

Most people make a nice hatch in the back floor

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Its not my vehicle, its the lads, so Im not about to add yet another line in the list of jobs added to "Dads Garage"

The two yellow relays under the drivers seat, it would be worth replacing them as they are cheap, I replaced my ones in 2016 when I first got my landy as it’s a worker bee and thought they are cheap enough to just replace and forget

Discodevon said:

The two yellow relays under the drivers seat, it would be worth replacing them as they are cheap, I replaced my ones in 2016 when I first got my landy as it’s a worker bee and thought they are cheap enough to just replace and forget

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Both glow plug relay and fuel pump relay are exactly the ssme

Back to square one..... Its a non starter again. We strongly suspect its fueling issues. Just draining the tank to fit a new fuel pump. We have replaced both relays, and cleaned up the connectors for the relay controlling the glow plugs, as it was arcing a bit, but made no difference. It will start to fire up on easy start for a few seconds. Im just draining the fuel via a fuel pressure gauge, fitted to the heat sensor hole on the FPR. The fuel is just diesel foam, and not liquid. WE have a new pump, so thats the first step, then I shall be testing for air leaks. We still get 4 bar at the gauge, but its not steady.

ODDIE POO PUMP said:

Tampering with exhaust system is an MOT fail.
Hopefully it will never run especially with no CAT fitted
Then again if you have an accident and the vehicle is inspected, doesn't have a CAT fitted then you are not insured and dependent on the damage caused in the event of an accident face a lengthy prison sentence...
But hey it's your lads land rover so why care...

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Has your carer left you with the laptop open again.......

tilly2 said:

Has your carer left you with the laptop open again.......

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Tis Bob, who is not allowed to play unsupervised ...

Update.... New pump fitted today. Thats resolved the foamy fuel, it now runs clear. Found a poor connection on the pump black wire, resolved that one... Still a non starter though... Unclipped and reclipped the crank sensor, and tried again, and it fired up.... but very lumpy. Stuck the nanocom on and found injector 2 and 5 showing open cct. Tried manually opening the injectors with the diagnostics, but 2 and 5 didnt click on test....... Lad told me he had replaced the injector harness, but with a cheap one. Whipped the top cover off and nothing jumping out at me... By now it was dark, so Ive left it for tomorrow, when I'll get the multimeter out and trace the wiring for poor connections.

+1 to SF for the pump wiring diagnosis, but it seems theres more than one issue....

Hi, seems that you found the culprit... no need to fiddle with multimeter, swap the plugs between injectors 1 - 2, 4 - 5 and fire them again with nanocom to see if the fault goes wirh the wires or not if you see what i mean.... at least you'll see if the injectors are working too, i've seen cheap injector harness which was DOA, only genuine LR is reliable in this area

Already done that SF, its the wiring.

One other thing I need to do is replace the fuel pump plug. The poor connection on the pump, was due to corrosion on the ground pin, and made it overheat. The plug was slightly melted. This site does a replacement kit, so will have to order a new one, and fit it soon....

Right.... further update, and conclusion...

She runs..... bought a new oem loom this morning from Craddocks, and collected. Thats all they had in stock. Changed the loom, and still missing injectors 2 and 5. Traced out the wiring and took off the red plug from the ECU. Sprayed contact cleaner on the plug, even though there was no visible oil.... Gave the plug a bit of a twist, and wiped off the cleaner. Started up first time, and runs sweet again...

Conclusion.... Initial non starting was getting worse over the last month..... which we can say was the issue with the pump, and its poorly connecting ground pin. That explains the intermittent noises and variations of the fuel pressure... New plug ordered this morning, and should arrive Tuesday. Just in time for the new fuel tank cradle, I have to pick up from Craddocks. The foamy deisel fuel delivery has gone, with the new pump fitting as well. Runs lovely can clear with no bubbles now....Plus I cant rule out that the crank sensor connector wasn't pushed home fully, as the boy did that one...

Misfire was the red plug on the ecu, not making a good connection, to the wiring that feeds the injector loom. All injectors now working fine, and no open cct faults.

All in all a learning experience on the TD5 system, and she's fixed, at least til the next fault comes along.

tilly2 said:

Misfire was the red plug on the ecu, not making a good connection, to the wiring that feeds the injector loom.

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Fingers crossed it was that cos it's quite common that the wiring which goes up to the head to be chafed and it can be intermittent, common points are shown in this thread https://www.aulro.com/afvb/discovery-2-a/143155-d2a-td5-misfiring-cutting-out-engine-harness.html ... let's hope it's not that but if the fault comes back at least you know what to check. Good luck

Hopefully, wont be that, as I checked the loom there when we first bought it. I replaced all that plastic loom conduit for new, as there were only token bits left.... I did check the cores at the time. I'd already done it on my Disco, so had loads left.

Thanks so much for posting the resolution to your problem, so many threads are started on here with no ending to the chapter

New pump plug finally fitted, plus a YRM tank guard....