rorykillam
Registered User
1992 Ford F250 NA 7.3L IDI
Hello folks this is my first post here so please bear with me. I'm going to try to keep this as concise as possible while still giving you all the information.
About 3 months ago now I found a crack in one of the fuel injector lines after an 800 mile or so trip, I had already been planning on replacing the GPs as I did not know how old they were. Replaced all the fuel injector lines (they were original lol) and replaced the GPs. The old ones were autolites but thankfully the truck has spent most of its life in the desert on the west coast so they were not swollen. Replaced them with Ultrapowers or something off rockauto (I know, I know foolish but I have learned since to only use ZD-9s). It took a lot of cranking with the fuel lines cracked to get her started, and since then she's been starting hard (at first it took 15 seconds of cranking 3-5 times with 3 minute intervals in-between, now it takes one try of 8-12 seconds after doing everything listed below). Sometime between then and now the wait to start light no longer illuminates for longer than a split second after I turn the key (sorry its warm here so It never stayed on long to begin with, I do remember it used to stay on for 3-6 seconds without clicking though) I have done the following:
Replaced all the rubber fuel lines with clear fuel resistant/high-heat rated line. Fuel is not draining and there are no visible/audible leaks or air bubbles in the lines. Fuel filter stays full and has less than 1000 miles on it.
Replaced starter (it was quite old and burnt out)
Replaced batteries (they were over 5 yrs old lol)
Replaced fender starter solenoid(at some point it fried and I had to jump it)
Replaced fusible links to GP relay
Checked maxi fuse K it (replaced it and nothing changed)
Replaced GP wiring harness with one from a reputable diesel parts website
Replaced GPs with motorcraft Beru ZD-9s
Checked WTS light bulb it's not blown
Checked every ground I could think of or find
Ohms Checked GPs, grounds, harnesses.
Checked voltage, 12.5v at fender starter solenoid, 12.5v at GP relay hot terminal and GP relay ignition terminal.
Replaced relay and controller twice, each one had the same voltage and each just begin to click when turn key to run. Intermittent voltage reading of 2-7v on glowplug side of controller with key in run, same reading at glowplugs while controller is cycling.
Any advice would be greatly appreciated I am really at a complete loss. Electrical is not my Forte by any means either haha. Does the engine temperature switch play any role in the GP controllers job? All my reading says no but I'm pretty sure my switch is bad ,going to replace that at first light tomorrow just because I am fairly certain it is shot or the terminals are corroded.
Short and sweet of it: replaced nearly every component in the glow plug system and the controller still seems to think the GPs are hot when they are not, can't find resistance anywhere either.
Also I am aware I could just wire a manual GP switch however at this point my pride won't let me give up haha
Thanks in advance, sorry for the long read.
Hello folks this is my first post here so please bear with me. I'm going to try to keep this as concise as possible while still giving you all the information.
About 3 months ago now I found a crack in one of the fuel injector lines after an 800 mile or so trip, I had already been planning on replacing the GPs as I did not know how old they were. Replaced all the fuel injector lines (they were original lol) and replaced the GPs. The old ones were autolites but thankfully the truck has spent most of its life in the desert on the west coast so they were not swollen. Replaced them with Ultrapowers or something off rockauto (I know, I know foolish but I have learned since to only use ZD-9s). It took a lot of cranking with the fuel lines cracked to get her started, and since then she's been starting hard (at first it took 15 seconds of cranking 3-5 times with 3 minute intervals in-between, now it takes one try of 8-12 seconds after doing everything listed below). Sometime between then and now the wait to start light no longer illuminates for longer than a split second after I turn the key (sorry its warm here so It never stayed on long to begin with, I do remember it used to stay on for 3-6 seconds without clicking though) I have done the following:
Replaced all the rubber fuel lines with clear fuel resistant/high-heat rated line. Fuel is not draining and there are no visible/audible leaks or air bubbles in the lines. Fuel filter stays full and has less than 1000 miles on it.
Replaced starter (it was quite old and burnt out)
Replaced batteries (they were over 5 yrs old lol)
Replaced fender starter solenoid(at some point it fried and I had to jump it)
Replaced fusible links to GP relay
Checked maxi fuse K it (replaced it and nothing changed)
Replaced GP wiring harness with one from a reputable diesel parts website
Replaced GPs with motorcraft Beru ZD-9s
Checked WTS light bulb it's not blown
Checked every ground I could think of or find
Ohms Checked GPs, grounds, harnesses.
Checked voltage, 12.5v at fender starter solenoid, 12.5v at GP relay hot terminal and GP relay ignition terminal.
Replaced relay and controller twice, each one had the same voltage and each just begin to click when turn key to run. Intermittent voltage reading of 2-7v on glowplug side of controller with key in run, same reading at glowplugs while controller is cycling.
Any advice would be greatly appreciated I am really at a complete loss. Electrical is not my Forte by any means either haha. Does the engine temperature switch play any role in the GP controllers job? All my reading says no but I'm pretty sure my switch is bad ,going to replace that at first light tomorrow just because I am fairly certain it is shot or the terminals are corroded.
Short and sweet of it: replaced nearly every component in the glow plug system and the controller still seems to think the GPs are hot when they are not, can't find resistance anywhere either.
Also I am aware I could just wire a manual GP switch however at this point my pride won't let me give up haha
Thanks in advance, sorry for the long read.
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