p38 diesel injection problem

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But when i put current to the relay points the pump works and she still only stars but dies. Glowplugs not working off key but it could be a relay.
 
Grrrrrr said:
I'd start with what doesn't work, like the in-tank punp.

The immobiliser should stop all fuel getting past the FIP so I wouldn't expect it to fire at all. If it does, even for a short time, then fuel must have got through somehow. Typically the diesel turns over but doesn't fire when it loses sync.
Click to expand...
As above, it's not an immobiliser issue as that would prevent it firing at all.
 
Soggybite3 said:
I get that. I have 12 v at feed to relay but not out. What would cause this
Click to expand...
Fuel pump on the diesel only runs under certain conditions which vary according to year.
When you say you have 12 volts to the relay, is that to the coil or one side of the contacts. I take it you are talking about the fuel pump relay?
 
Fuel pump relay yes. one contact has power but not the other. if i bridge the 2 i get fuel but she still dies after starting. So why no power out to pump, Could it be the inertia switch which i have pressed but could it be faulty
 
Soggybite3 said:
I get that. I have 12 v at feed to relay but not out. What would cause this
Click to expand...
The glow plug relay?
One side will be powered when needed and the other maybe a live feed to the plugs that is connected from within the relay. You can check a relay with a 12v battery and a DVM. Power the relay to switch and check continuity on the other two connectors.
A relay can work but the connecting surface that makes the circuit can burn inside of it. Everytime the contacts inside the relay open a small particle of the surface is pulled away and eventually leaves a damaged contact surface.
Do you have another relay you can try?
Have you checked to see if there is current at a glow plug?🤔
 
Mark Piercy said:
The glow plug relay?
One side will be powered when needed and the other maybe a live feed to the plugs that is connected from within the relay. You can check a relay with a 12v battery and a DVM. Power the relay to switch and check continuity on the other two connectors.
A relay can work but the connecting surface that makes the circuit can burn inside of it. Everytime the contacts inside the relay open a small particle of the surface is pulled away and eventually leaves a damaged contact surface.
Do you have another relay you can try?
Have you checked to see if there is current at a glow plug?🤔
Click to expand...
I think he was talking about the fuel pump relay?
 
Mark Piercy said:
The glow plug relay?
One side will be powered when needed and the other maybe a live feed to the plugs that is connected from within the relay. You can check a relay with a 12v battery and a DVM. Power the relay to switch and check continuity on the other two connectors.
A relay can work but the connecting surface that makes the circuit can burn inside of it. Everytime the contacts inside the relay open a small particle of the surface is pulled away and eventually leaves a damaged contact surface.
Do you have another relay you can try?
Have you checked to see if there is current at a glow plug?🤔
Click to expand...
Sorrry it is the relay for the electric fuel pump. I also have a glow plug issue which has been wired direct to battery for test purpose but will be removing the inlet on the weekend to access fip and glowplugs. I believe the relay for that is in the box behind the battery. not sure which one or if there is only 1 cant remember but will be checking. My real question has been that why do i only have power into pump relay and not out. I will be checking the inertia switch as well. Beyond that i am puzzled
 
Soggybite3 said:
Sorrry it is the relay for the electric fuel pump. I also have a glow plug issue which has been wired direct to battery for test purpose but will be removing the inlet on the weekend to access fip and glowplugs. I believe the relay for that is in the box behind the battery. not sure which one or if there is only 1 cant remember but will be checking. My real question has been that why do i only have power into pump relay and not out. I will be checking the inertia switch as well. Beyond that i am puzzled
Click to expand...
Don't apologise matey, have you tried another relay in it is place to rule it out?
There is a large plug under the fuse box that you could check for corrosion. I'm not sure what comes and goes through the plug but a check over couldn't harm.
The fusebox is removed quite easily with its coloured plugs.
👍
 
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