[Mark Winfield]

Hi All,

1995 6.5 Diesel safari trek
I'm trying to sort my no fuel and no glow plug issue.

I only have 4.5 v coming into the OPS and the fuel pump relay.
I'm assuming they should be 12v

Earth issue maybe? Where is the fuel pump relay earthed?

thanks

Mark

 

[OkDually]

Welcome to DieselPlace

 

[Mark Winfield]

Hey thanks.

Shouldve written this first.
I have a Safari Trek 6.5l Diesel 1995
I've had the top off and upon reassembly find that I have no glow plugs or fuel.
I have no clicking relays either.
These all worked before head off.

I have power to the glow plug relay(red wire) and from ignition on the pink wire. I have no signal from the yellow wire.

The fuel pump works when I by pass the relay and is providing good flow.

Maybe something wasn't reconnected during reasembly? It beats me!

Any help appreciated.

Mark

 

[Mark Winfield]

Should ad that I haveno fuel at the injectors either.

 

[Glagulator]

Look for ground wires that were bolted to the engine.
They are usually at the rear of the engine head.
There is very little info on the Safari Trek 6.5l Diesel
so you just have to track things down.

 

[Mark Winfield]

Thanks Glagulator. Looking there now

 

[macdaddyof9]

There are two ground wires that bolt on with the intake manifold on the right rear of my truck. I can send a picture if you can't find the grounds

 

[Mark Winfield]

There are two ground wires that bolt on with the intake manifold on the right rear of my truck. I can send a picture if you can't find the grounds

Thanks, I'll have a look tomorrow.
Where do these wires originate from? Pictures would be great. If you have the time , that is.

Mark

 

[OkDually]

Thanks, I'll have a look tomorrow.
Where do these wires originate from? Pictures would be great. If you have the time , that is.

Mark

Links for grounds and more can be found in our 6.5L FAQ page listed at the top of this forum section.

Grounds-Grounds-Grounds The importance of good grounds.....

This is not completely 6.5 related but I think it's very relavent. We always hear the people in the know around here (gmctd in particular) talking about checking your grounds for almost every problem under the sun..... Q. "Yeah I got a slow leak in my passenger's side rear tire, what could...

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[Mark Winfield]

Thanks for these pics. I had reseated the Battery Earth and Engine earth strap. PCM Earth good too. Will chase down the others today.
Mark

 

[JMJNet]

On a regular truck in 95 model year, the OPS controls the LP when engine is running.
Mind you, the gauge will still work but the LP is not if the OPS is bad.
Sounds like the LP is working but it may not pump when engine is running which point to OPS.

 

[Mark Winfield]

I think I've tracked it to low voltage coming into the fuel pump relay. Only showing 4V. Must have a short, I'm guessing. Any ideas?

 

[OkDually]

I think I've tracked it to low voltage coming into the fuel pump relay. Only showing 4V. Must have a short, I'm guessing. Any ideas?

Trace the wires from the lift pump back up looking for any rub through wire insulation issues, rodent damage, etc.
Also, try disconnecting the fuel heater wires located on the bottom of the fuel filter manager.
The heater element is known to short out

 

[macdaddyof9]

Is the 4 volts on the contact pin? or the coil pin? The coil power is from the crank fuse, contact power is from ecm b fuse.

 

[JMJNet]

On a 95, the relay was not wired correctly, for some reason.
However, I have never diagnose it, in terms of how much voltage should come out.

Did you measure it when engine is running?

 

[Mark Winfield]

Trace the wires from the lift pump back up looking for any rub through wire insulation issues, rodent damage, etc.
Also, try disconnecting the fuel heater wires located on the bottom of the fuel filter manager.
The heater element is known to short out

I'm not sure mine has a fuel heater? 1996? Safari trek?I'll have a look. Checking that wire now for rubbing etc. Maybe I'll run anoter wire up to the fuse board.

 

[OkDually]

I'm not sure mine has a fuel heater? 1996? Safari trek?I'll have a look. Checking that wire now for rubbing etc. Maybe I'll run anoter wire up to the fuse board.

Located on the very bottom of your fuel filter manager is the fuel heater. The black canister contains the heater element.
You'll see the wire connector for it.

 

[Mark Winfield]

On a 95, the relay was not wired correctly, for some reason.
However, I have never diagnose it, in terms of how much voltage should come out.

Did you measure it when engine is running?

Located on the very bottom of your fuel filter manager is the fuel heater. The black canister contains the heater element.
You'll see the wire connector for it.

Ah yes , Found it. Wires seem fine. disconnected it. No change

 

[OkDually]

Ah yes , Found it. Wires seem fine. disconnected it. No change

The Oil Pressure Sensor (OPS) feeds power to the lift pump. Over time the Sensor becomes weak and brittle and the contacts inside can no longer support the power needs of the lift pump..
I would replace the OPS next ( Use only AC/Delco brand )

 

[dieselolds]

X2 on using acdelco whenever possible .👍