Manual glow plug control

Ferdy Mint · Nov 22, 2021

First chilly morning, my 03 was crank no start, lots of smoke. No voltage drop from the GPM, so that's the cause. I know how to fix that. We have spare snowmobile GPRs on the shelf.

But this truck started fine for months till we got down into the 40s. I dislike seeing the GPR cycle when it's not cold, sucking down battery and wasting GP life.

Has anyone put their GPM on a switch? I'd leave it turned off for 95% of the year, here in Texas. I have upfitter switches that will go on the dash soon for lighting, could add the GPM there.

Pic for context, waited 7 months for this truck because the PO wanted a 2022 and it took that long to get one.

Ferdy Mint · Nov 22, 2021

Looks like I only need to interrupt the small ground wire on the GPR, and run that to a momentary switch that I can reach from the driver seat.

lotzagoodstuff · Nov 23, 2021

I agree that watching the batteries pull down on the gage heating GPs unnecessarily when its warm enough not to need them seems, well unnecessary

I've heard the mandatory and extended dwell of the GPs was related to cold start emissions. I don't know anybody who's done it but I can't see any reason why it wouldn't work.

By the way: if you aren't already running the White Rogers GPR, you should consider it.

Kevin 007 · Nov 23, 2021

Manual glow control (especially on the obs truck) can really help increase the life of the under cover harnesses, which otherwise become a problem sooner or later. Not to mention the reduced strain on the glow plugs themselves and the alternator

greenskeeper · Nov 23, 2021

Ferdy Mint said:
Looks like I only need to interrupt the small ground wire on the GPR, and run that to a momentary switch that I can reach from the driver seat.

as long as you have the old style relay, and not a glow plug module, then you are correct in that you only have to run the relay ground wire controlled by the PCM to a switch in the cab. Break that connection and the relay won't close. You will get a soft code for relay control which shouldn't illuminate the CEL.

This is one of the first mods I did to both my trucks. I also added an LED next to the switch on the powered side of the relay to prove the relay is energized.

greenskeeper · Nov 23, 2021

lotzagoodstuff said:
I agree that watching the batteries pull down on the gage heating GPs unnecessarily when its warm enough not to need them seems, well unnecessary I've heard the mandatory and extended dwell of the GPs was related to cold start emissions. I don't know anybody who's done it but I can't see any reason why it wouldn't work.

By the way: if you aren't already running the White Rogers GPR, you should consider it.

It's all about cold start emissions. With my toggle switch installed on the relay ground wire (PCM) I am able to kill power to the glow plugs as soon as the engine fires. Saves tons of wear on the glow plug components and gives the neighbors a nice breath of that sweet cold start diesel smoke. Not to mention that anytime it's 45F or higher the glow plugs aren't needed for a cold start.

greenskeeper · Nov 23, 2021

Kevin 007 said:
Manual glow control (especially on the obs truck) can really help increase the life of the under cover harnesses, which otherwise become a problem sooner or later. Not to mention the reduced strain on the glow plugs themselves and the alternator

Any 7.3 vintage (OBS or SD) can benefit from this mod by preventing unnecessary wear and tear, and battery drain.

greenskeeper · Nov 23, 2021

Side note, if you're glow plug relay quits, a quick fix to get the engine running is to jump the large terminals with the clamp from a set of jumper cables, which we all carry right?

tonyj54 · Nov 27, 2021

When I bought my 1986 in 2014, the controller still worked fine. When it stopped working, around 2017, the truck became nearly impossible to start. I was loathe to replace the controller for two reasons, the cost and the location, beneath the Banks Sidewinder turbo installed by a previous owner. I was dumbfounded that, in Florida, I had to use starter fluid to get him started. I recently installed a heavy-duty pushbutton to warm GPs manually. Now, I give it a 3-4 count in warm months, and 5-6 on cool or cold days, and he hits on first turn of the key. I'll not install another automatic controller while I own this truck.

Manual glow plug control

Ferdy Mint

Full Access Member

Attachments

Ferdy Mint

Full Access Member

lotzagoodstuff

Supporting Member

Kevin 007

Full-floater

greenskeeper

Full Access Member

greenskeeper

Full Access Member

greenskeeper

Full Access Member

greenskeeper

Full Access Member

tonyj54

Registered User

Similar threads

Latest posts

Forum statistics

Staff online

Members online

Share this page