Where to get a GP Controller (1988)

HammerDown

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GP Controller is bad... who is a reputable source for a replacement?
I'm not home and that's where my Haynes 7.3 Diesel Repair Manual is ... trying to diagnose the problem away from home.
Symptom: dead cold next morning engine, key 'on' ... 'Wait To Start Light' gives a good 8-10 seconds.
Light 'out'... crank-crank-crank = no start but puffs of smoke out tailpipe so it is getting fuel.
Leave key-on, I give the air cleaner a 'sniff' of Starting Fluid and the engine fires up, all is good.
Once warm, engine starts as usual.
All I have with me is a test light... I'm thinking the GP Controller failed but, the Wait To Start Light seems to be working as usual.
Who is selling a quality replacement?
Thanks for any feedback!
 
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Nero

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I've had good success with Napa branded ones in the past, but Ford dealers still sell them. I have a genuine Motorcraft one in my truck and my dad's. Both less than a year old.
 

HammerDown

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I've had good success with Napa branded ones in the past, but Ford dealers still sell them. I have a genuine Motorcraft one in my truck and my dad's. Both less than a year old.
Yep, local Ford dealer can have one for me when I return home Friday $203.69 plus 6% sales tax.
EDIT > > > wow Napa price $132.99 but do I take the chance on a probably made in china part?
 

Nero

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Yep that sounds about right.
 

Old Goat

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You can hook up a temporary manual GP switch instead of using starting fluid.

post 18 in this thread tells how to do it.
leave it that way, or spend the big bucks on a new controller.



Goat
 

BeastMaster

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Watch your voltmeter when the glow plugs are cycling.

A 200 Amp load on the battery makes a noticeable voltage drop.

For me, the most noticeable thing is the change of pitch of whine in my electric Carter fuel lift pump .

No voltage perturbation?

You may have open contacts on your GP relay, all bad plugs, or bad connection somewhere.

Time to get your light and verify your plugs are getting power.

One thing I have got to do is install some sort of tie-in to connect an under hood remote start/run bypass just for this kind of thing.
 

HammerDown

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Watch your voltmeter when the glow plugs are cycling.

A 200 Amp load on the battery makes a noticeable voltage drop.

For me, the most noticeable thing is the change of pitch of whine in my electric Carter fuel lift pump .

No voltage perturbation?

You may have open contacts on your GP relay, all bad plugs, or bad connection somewhere.

Time to get your light and verify your plugs are getting power.

One thing I have got to do is install some sort of tie-in to connect an under hood remote start/run bypass just for this kind of thing.
I did diagnose a bad GP Controller.
Question is: at 1/2 the cost, how are the aftermarket GP controllers from let's say Napa vs the Ford Controller?
 

Nero

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Like any aftermarket part, your mileage can vary. I ran a Napa gpc on my truck for about 10 years before it failed, only reason I went with Motorcraft was because a friend of mine worked at a dealer so I got it for employee discount price.
My dad had a gpc fail within 30 days (Napa) and they warranted it out. Lasted until we sold that particular truck, about 6 years.
Only reason we used a Motorcraft on his other truck was because we diesel swapped it, and the donor engine didn't have a gpc on it.
 

HammerDown

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Like any aftermarket part, your mileage can vary. I ran a Napa gpc on my truck for about 10 years before it failed, only reason I went with Motorcraft was because a friend of mine worked at a dealer so I got it for employee discount price.
My dad had a gpc fail within 30 days (Napa) and they warranted it out. Lasted until we sold that particular truck, about 6 years.
Only reason we used a Motorcraft on his other truck was because we diesel swapped it, and the donor engine didn't have a gpc on it.
OEM since purchased the truck new lasted until 2000.
Replaced it with another OEM that lasted 23 years!
Nappa is a three year warranty for 1/2 the price. My biggest fear is it fails and burns-up 8 Beru glowplugs $$$$
 

Black dawg

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Have not seen one of these controllers fail and burn out the plugs.

I will say, dont be surprised when the OEM ford part is just reboxed.......
I have used several of the napa Echlin ones without issue, but it does look like the controller that is offered in the echlin line now, is the same one that was the napa diesel line not to long ago.....

It is pretty amazing comparing the electronics inside the controller from one of the modern ones to an old original one. Much less stuff in there.....
 

BeastMaster

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Good luck. Watch for "infant mortality" failure of the relay contacts welding shut.

I had two brand new glow plug control relays weld their contacts shut on me.

One was NAPA/ Echlin brand, the other was a Ford Motor craft, professionally installed.

I got frustrated enough to replace the controller with a white-rodgers industrial contactor and a manual pushbutton .

I was so frustrated. I could tell by my voltmeter that the glow plugs were still on, despite no power to the relay coil. The first time it happened, it took out my alternator, the second time, it took out a couple of glow plugs before I could get the batteries disconnected.

The glow plug relay contact is fed off the main battery rail. Turning the key off only kills coil power.
 

HammerDown

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Well
Good luck. Watch for "infant mortality" failure of the relay contacts welding shut.

I had two brand new glow plug control relays weld their contacts shut on me.

One was NAPA/ Echlin brand, the other was a Ford Motor craft, professionally installed.

I got frustrated enough to replace the controller with a white-rodgers industrial contactor and a manual pushbutton .

I was so frustrated. I could tell by my voltmeter that the glow plugs were still on, despite no power to the relay coil. The first time it happened, it took out my alternator, the second time, it took out a couple of glow plugs before I could get the batteries disconnected.

The glow plug relay contact is fed off the main battery rail. Turning the key off only kills coil power.
Well, that was a pleasant read.
 

HammerDown

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Well, maybe the Napa brand was a mistake. Napa GP Controller clicking like crazy and the 'Wait to Start Light" only on for a blink of an eye... but I installed it on a warm/hot engine.
Clearly OEM VS aftermarket not the same on the underside, 1/3 the epoxy as OEM.
Dead cold start coming tomorrow morning.
 

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HammerDown

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Have not seen one of these controllers fail and burn out the plugs.

I will say, dont be surprised when the OEM ford part is just reboxed.......
I have used several of the napa Echlin ones without issue, but it does look like the controller that is offered in the echlin line now, is the same one that was the napa diesel line not to long ago.....

It is pretty amazing comparing the electronics inside the controller from one of the modern ones to an old original one. Much less stuff in there.....
Correct... the OEM has full epoxy underneath with more electronics and the Napa has much less going on.
But of course the paperwork with the aftermarket states it "designed to meet and exceed the original parts performance"
Have not seen one of these controllers fail and burn out the plugs.

I will say, dont be surprised when the OEM ford part is just reboxed.......
I have used several of the napa Echlin ones without issue, but it does look like the controller that is offered in the echlin line now, is the same one that was the napa diesel line not to long ago.....

It is pretty amazing comparing the electronics inside the controller from one of the modern ones to an old original one. Much less stuff in there.....
 

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