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Discussion Starter · #41 ·
This may sound bad but in all my years of backyard mechanics I never learned how to do electrical or even use a multimeter. I’m fairly good at identifying when something is off or wrong with a system but the rest is kind of Greek to me.

since this harness is a bit jacked I’m trepidatious but if these are the cause of my problems I should probably give it a shot.
 

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Those are the PCM ground wires and could cause all kinds of problems if there is an intermittent connection.
I would pull on them together since they are on 1 ring terminal, hopefully.
I have never experienced or read of what your WTS lamp is doing.
The WTS lamp is lit by the 12v. going to the glow plugs.
If the glows are glowing the WTS lamp is lit.
The GLOW fuse is there to protect the gauge cluster and PCM from that voltage.
I'm guessing that wiring mess at the GPR is at least part of the problem.
 
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Discussion Starter · #44 ·
Do you happen to have a picture of what a 95 glow plug relay should look like at the plug into the controller? I can’t figure out schematics to save my life. I can decently solder wires and hear shrink them. My plan for that is to take that mess apart and solder stuff correctly.

On the PCM grounds I’m going to try to trace them back far as I can, cut them or pull off the eyelet. Then find a slightly thicker gauge wire. Twist those two PCM wires together and solder them to a thicker gauge wire and ground them where I can see them.

Do those sound like good ideas?
 

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For what it's worth I also had an unusual electrical issue that caused intermittent engine cut out. It turned out to be a burnt out pin in one of the main wiring harness connectors. The method of diagnosis that worked for me might apply here also. If you can get it running grab/poke/prod the wiring harness and see if you can induce the engine to cut out and see if you can narrow it down from there.
 

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Here you go.

Rectangle Parallel Font Slope Number
 
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Was the ground hanging loose, not bolted down?
 

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Discussion Starter · #52 ·
Just updating since I hate when these threads just stop before a success or giving up.

I’m still stumped.

so far:

Problem: no start or rare start. Will run for max five to ten minutes. Still there. Have to bleed the fuel system after it starts at the injectors.

2 PMDs used either or. Have seen both start it briefly. I am not using either remote harness I have. Both PMDs on heat sinks with pink pad.

replaced fuel lines front to back. Currently one smaller bubble in the clear return line. Tank sender looked newer. Replaced the sock with AC delco. Replaced the OPS (not ac delco).

2 new batteries with 700 cca.

When it stops running I crack a line and it looks like a no fuel situation but not entirely sure. Have to bleed the system every time it stops.

pump was replaced by a prior owner. Looks newer. Ground for pmd present on pump.

cleaned grounds and regrounded some (bad ground on back passenger from block to frame. This is replaced. New eyelet on PCM ground and regrounded. I get check engine light and all other lights in run position and crank position.

new oil change and filter (for fun)

Starter replaced by prior owner.

glow plug system a mess. Currently jumping terminals. There is no wait to start light. Going to see about cleaning up the wiring mess there today.

jumping lift pump manually To keep it running.

gutted the fuel shutoff selinoid because it wasn’t retracting in the run position.

cleaned/checked connectors at main harness. Looked good.

All fuses replaced under hood. Removed acccessories on back of fuse box. No blown fuses now.
 

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Just updating since I hate when these threads just stop before a success or giving up.

I’m still stumped.

so far:

Problem: no start or rare start. Will run for max five to ten minutes. Still there. Have to bleed the fuel system after it starts at the injectors.

2 PMDs used either or. Have seen both start it briefly. I am not using either remote harness I have. Both PMDs on heat sinks with pink pad.

replaced fuel lines front to back. Currently one smaller bubble in the clear return line. Tank sender looked newer. Replaced the sock with AC delco. Replaced the OPS (not ac delco).

2 new batteries with 700 cca.

When it stops running I crack a line and it looks like a no fuel situation but not entirely sure. Have to bleed the system every time it stops.

pump was replaced by a prior owner. Looks newer. Ground for pmd present on pump.

cleaned grounds and regrounded some (bad ground on back passenger from block to frame. This is replaced. New eyelet on PCM ground and regrounded. I get check engine light and all other lights in run position and crank position.

new oil change and filter (for fun)

Starter replaced by prior owner.

glow plug system a mess. Currently jumping terminals. There is no wait to start light. Going to see about cleaning up the wiring mess there today.

jumping lift pump manually To keep it running.

gutted the fuel shutoff selinoid because it wasn’t retracting in the run position.

cleaned/checked connectors at main harness. Looked good.

All fuses replaced under hood. Removed acccessories on back of fuse box. No blown fuses now.
If you still have to bleed the fuel system then you have an air in fuel issue somewhere that needs to be addressed.
Go through the ENTIRE fuel system from tank to Injection pump.

replace any rubber lines that need attention, look for any loose clamps, wet lines, weeps , etc...make sure the tank sock is not plugged,
Open your fuel cap. Do you hear a large "Whoosh" sound? if so, then you need to modifiy your fuel cap or replace it with a Diesel rated fuel cap.
 

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Discussion Starter · #54 ·
Fuel issue is one of my first thoughts but I’ve replaced all lines. From the tank to the LP it’s all new steel prebent lines. From LP to FFM it’s all new rubber lines. And from FFM to IP I’ve raised the FFM and added all new rubber lines.

the only thing I didn’t replace was the sending unit in the tank. I did replace the sock with AC delco, but the other one didn’t look clogged at all.

I’ve replaced the return line with clear tube and I’m getting a small bubble or no bubble.

the area where I’m having the issue is after it runs for a minute or two I’ve got to bleed the lines from the IP to the injectors.
 

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Fuel issue is one of my first thoughts but I’ve replaced all lines. From the tank to the LP it’s all new steel prebent lines. From LP to FFM it’s all new rubber lines. And from FFM to IP I’ve raised the FFM and added all new rubber lines.

the only thing I didn’t replace was the sending unit in the tank. I did replace the sock with AC delco, but the other one didn’t look clogged at all.

I’ve replaced the return line with clear tube and I’m getting a small bubble or no bubble.

the area where I’m having the issue is after it runs for a minute or two I’ve got to bleed the lines from the IP to the injectors.
Check your injector return lines. If they are cracked or have loose clamps you may have an air intrusion
 

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Return lines look good except cannot see easily under the turbo. No bubbles in the clear tube except the small one.
Did you replace the feed line from the FFM to the IP?
 

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Basically everything is new, tank to IP, except the sending unit which looked newer. The sock has been changed too to AC deco.
Double check all clamps are tight and make sure the hose is on correctly and not shifted to one side or another possibly creating a weak seal.
Also check for any kinked hoses
 
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