Glow plug controller troubleshooting 6.9idi
Logistics Pro
Joined: Jun 2017
Posts: 3,954
Likes: 511
From: Edmond, OK
I thought 87 was the last year of the 6.9l. I could be wrong. 
Regardless, if you just replaced the GPs then chances are they're good. Then again, you mentioned that you had to use ether to get the engine started. Ether + GPs = BAD!
If you have to use ether make sure you don't use the GPs.
Regardless, if you just replaced the GPs then chances are they're good. Then again, you mentioned that you had to use ether to get the engine started. Ether + GPs = BAD!
If you have to use ether make sure you don't use the GPs.
Fleet Mechanic
Joined: Nov 2022
Posts: 1,697
Likes: 416
Fleet Mechanic
Joined: Nov 2022
Posts: 1,697
Likes: 416
i ain't rite
Joined: Mar 2005
Posts: 65,483
Likes: 5,542
From: Marlboro Mental Hospital.
i believe the 84 had the relay on top of that cylinder that screws into the block.
been a LONG time since i messed with an old style controller. probably close to 30 years or more.
been a LONG time since i messed with an old style controller. probably close to 30 years or more.
Fleet Mechanic
Joined: Nov 2022
Posts: 1,697
Likes: 416
There is also the old style one on the back of the block
i ain't rite
Joined: Mar 2005
Posts: 65,483
Likes: 5,542
From: Marlboro Mental Hospital.
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Fleet Mechanic
Joined: Sep 2016
Posts: 1,519
Likes: 224
From: Nevada
Yes, that is the Glow Plug Relay.
My 86 has it on the Passenger fender.
87 last year for the 6.9, Ford changed the
Controller to the new style as well changing the
Glow Plugs from the ZD-1 (spade) to the ZD-9
(Bullet connectors)
Charlie
My 86 has it on the Passenger fender.
87 last year for the 6.9, Ford changed the
Controller to the new style as well changing the
Glow Plugs from the ZD-1 (spade) to the ZD-9
(Bullet connectors)
Charlie
Fleet Mechanic
Joined: Nov 2022
Posts: 1,697
Likes: 416
Would you say my controller is bad? I can't turn my plugs on, not even the indicator light, also no click
Fleet Mechanic
Joined: Nov 2022
Posts: 1,697
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Yeah, I've got the spades
i ain't rite
Joined: Mar 2005
Posts: 65,483
Likes: 5,542
From: Marlboro Mental Hospital.
check for power to one of the large terminals on the relay.
if you have power to it, jump the two large terminals for 10 seconds on the cold engine and see if it starts.
if it don't glow plugs are bad. if it does, either relay is bad, or it is not getting signal through the two small terminals ot turn it on.
Fleet Mechanic
Joined: Nov 2022
Posts: 1,697
Likes: 416
could be controller, could be bad relay, or it could be no power going to them.
check for power to one of the large terminals on the relay.
if you have power to it, jump the two large terminals for 10 seconds on the cold engine and see if it starts.
if it don't glow plugs are bad. if it does, either relay is bad, or it is not getting signal through the two small terminals ot turn it on.
check for power to one of the large terminals on the relay.
if you have power to it, jump the two large terminals for 10 seconds on the cold engine and see if it starts.
if it don't glow plugs are bad. if it does, either relay is bad, or it is not getting signal through the two small terminals ot turn it on.
i ain't rite
Joined: Mar 2005
Posts: 65,483
Likes: 5,542
From: Marlboro Mental Hospital.
it could be the controller, or it could be a bad wire between controller and relay. remember, those wires are 39 year old.
with key on, you should also have power to one of the small terminals on the relay. the other small terminal is ground.
if i remember correctly, the controller shorts out to ground which sends a ground signal to the relay to close it and power the glow plugs.
with key on, you should also have power to one of the small terminals on the relay. the other small terminal is ground.
if i remember correctly, the controller shorts out to ground which sends a ground signal to the relay to close it and power the glow plugs.
Fleet Mechanic
Joined: Nov 2022
Posts: 1,697
Likes: 416
it could be the controller, or it could be a bad wire between controller and relay. remember, those wires are 39 year old.
with key on, you should also have power to one of the small terminals on the relay. the other small terminal is ground.
if i remember correctly, the controller shorts out to ground which sends a ground signal to the relay to close it and power the glow plugs.
with key on, you should also have power to one of the small terminals on the relay. the other small terminal is ground.
if i remember correctly, the controller shorts out to ground which sends a ground signal to the relay to close it and power the glow plugs.