Check Engine Light- constant on
Super Moderator
Joined: May 2004
Posts: 29,380
Likes: 118
From: Central Coast of CA
I was referring to the bridge on the GPR.
Before Ford started using the GPCM, the Cali emissions prepped E99 trucks (E = "Early") came with GPR's that had a bridge on them, like was referred to earlier in this thread.
Pete (we have several Pete's, the one I'm referring to goes by @duck fan here) was telling me about an E99 truck he was working on that belongs to Andy (aka Fat Diesel) and he had a similar problem, if not the same problem (foggy memory, sorry) and it came down to the bridge on the GPR not being there for Andy's California truck.
Do like Pik stated and replace the bridge that he identified as missing when referencing one of the pictures you posted.
Stewart
PS - Whether your Ex came off the line that way, or someone changed it, there is a way to fix it. I'm thinking based on the info you've posted, treat your rig like an E99 F250 with a California emissions prep, and get it back to that standard to see if it fixes the DTC.
Before Ford started using the GPCM, the Cali emissions prepped E99 trucks (E = "Early") came with GPR's that had a bridge on them, like was referred to earlier in this thread.
Pete (we have several Pete's, the one I'm referring to goes by @duck fan here) was telling me about an E99 truck he was working on that belongs to Andy (aka Fat Diesel) and he had a similar problem, if not the same problem (foggy memory, sorry) and it came down to the bridge on the GPR not being there for Andy's California truck.
Do like Pik stated and replace the bridge that he identified as missing when referencing one of the pictures you posted.
Stewart
PS - Whether your Ex came off the line that way, or someone changed it, there is a way to fix it. I'm thinking based on the info you've posted, treat your rig like an E99 F250 with a California emissions prep, and get it back to that standard to see if it fixes the DTC.
Super Moderator
Joined: May 2004
Posts: 29,380
Likes: 118
From: Central Coast of CA
I tagged Pete, so hopefully he'll drop in and post.
Stewart
Super Moderator
Joined: May 2004
Posts: 29,380
Likes: 118
From: Central Coast of CA
I guess it's possible too, and I gotta wonder if for the first units off the line, Ford made Excursions with an E99 GPR California emissions F-series setup because the GPCM's weren't available immediately.
With a build date of October 1999, you have the earliest Excursion I've ever seen on the forum.
I still think someone changed out your engine, harness, and PCM tho.
Can you get a Carfax on it and see the cause for the salvage title is listed? I'm curious if there was fire or flood damage that necessitated their replacement.
Stewart
With a build date of October 1999, you have the earliest Excursion I've ever seen on the forum.
I still think someone changed out your engine, harness, and PCM tho.
Can you get a Carfax on it and see the cause for the salvage title is listed? I'm curious if there was fire or flood damage that necessitated their replacement.
Stewart
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Mountain Pass
Joined: Jun 2007
Posts: 103
Likes: 5
From: Anaheim
I ran a carfax and it doesn't show any details about what may have happened. It shows no structural damage nor airbag deployment. I remember the guy I bought it from, who was the one who restored it, said it rolled onto the driver's side. I have found residual glass over the years but I don't believe the engine was replaced.
It's a Van Gogh
Joined: Feb 2010
Posts: 7,819
Likes: 1,336
From: Elk Grove, CA
Looking at this pic, I'm thinking the GPR is OE Ford, untouched since install in Kentucky. Nothing about that harness says a GPCM used to live there.
I'd start with ohming out the driver side glow plugs by the method Pikachu suggested. The pins on the UVCH are small so it can be a pain to get the probe on there. To make it easy you could get a pigtail like THIS and read off the exposed wires.
That's probably it, but if they check out next I'd want to see the PCM code to see if that was swapped.
I'd start with ohming out the driver side glow plugs by the method Pikachu suggested. The pins on the UVCH are small so it can be a pain to get the probe on there. To make it easy you could get a pigtail like THIS and read off the exposed wires.
That's probably it, but if they check out next I'd want to see the PCM code to see if that was swapped.
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Super Moderator
Joined: May 2004
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Likes: 118
From: Central Coast of CA
The harness wouldn't.
If someone decided to remove the GPCM and replace it with a GPR, or if someone transplanted a replacement 7.3 into the Ex and the replacement engine had a GPR, then the engine harness would have to be changed to accommodate the GPR because IIRC, Joe (who has done this mod) said the harness couldn't be modified to accept the GPR.
Honestly tho I still can't help but wonder if the first few Excursions off the line didn't somehow have the California style GPR because the module wasn't quite yet ready.
Stewart
If someone decided to remove the GPCM and replace it with a GPR, or if someone transplanted a replacement 7.3 into the Ex and the replacement engine had a GPR, then the engine harness would have to be changed to accommodate the GPR because IIRC, Joe (who has done this mod) said the harness couldn't be modified to accept the GPR.
Honestly tho I still can't help but wonder if the first few Excursions off the line didn't somehow have the California style GPR because the module wasn't quite yet ready.
Stewart
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Mountain Pass
Joined: Jun 2007
Posts: 103
Likes: 5
From: Anaheim
OK, hubby tested the driver side glow plug resistance and all of them but one read 1.2ohms. The front most one (closest to the bumper) was 3.8 so it appears we have our culprit.
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Mountain Pass
Joined: Jun 2007
Posts: 103
Likes: 5
From: Anaheim
Hi guys. I know it's been awhile. I had that one glow plug changed a few weeks ago and the code was cleared. The problem is the SES light came right back on and now I have three fault codes:
P1391 Glow plug circuit low input, bank #1 (right) Open/short/miswired circuit, faulty relay, glow plugs.
P1395 Glow plug monitor fault, bank #1 One or more glow plugs failed or circuit fault.
P1396 Glow plug monitor fault, bank #2 One or more glow plugs failed or circuit fault.
Anyone have any suggestions? I'm still trying to get this darned thing smogged in So Cal so I can get it registered/insured here.
P1391 Glow plug circuit low input, bank #1 (right) Open/short/miswired circuit, faulty relay, glow plugs.
P1395 Glow plug monitor fault, bank #1 One or more glow plugs failed or circuit fault.
P1396 Glow plug monitor fault, bank #2 One or more glow plugs failed or circuit fault.
Anyone have any suggestions? I'm still trying to get this darned thing smogged in So Cal so I can get it registered/insured here.
Fleet Mechanic
Joined: Oct 2010
Posts: 1,997
Likes: 206
From: South Eastern Michigan
Hi guys. I know it's been awhile. I had that one glow plug changed a few weeks ago and the code was cleared. The problem is the SES light came right back on and now I have three fault codes:
P1391 Glow plug circuit low input, bank #1 (right) Open/short/miswired circuit, faulty relay, glow plugs.
P1395 Glow plug monitor fault, bank #1 One or more glow plugs failed or circuit fault.
P1396 Glow plug monitor fault, bank #2 One or more glow plugs failed or circuit fault.
Anyone have any suggestions? I'm still trying to get this darned thing smogged in So Cal so I can get it registered/insured here.
P1391 Glow plug circuit low input, bank #1 (right) Open/short/miswired circuit, faulty relay, glow plugs.
P1395 Glow plug monitor fault, bank #1 One or more glow plugs failed or circuit fault.
P1396 Glow plug monitor fault, bank #2 One or more glow plugs failed or circuit fault.
Anyone have any suggestions? I'm still trying to get this darned thing smogged in So Cal so I can get it registered/insured here.
Elder User
Joined: Sep 2011
Posts: 979
Likes: 4
From: Vancouver
The more likely culprit is the "42 pin" connector. The reason for this conclusion is that both sides of the engine are now showing a trouble. The cable that connects to this has to be removed to remove the valve cover. I suggest disconnecting the cable again and inspecting both sides of the connector for corrosion, clean with alcohol (you may also drink some while doing this). When tightening the bolt that holds the connector in place, apply a small amount of engine or other oil to the bolt thread to ensure complete installation.
I have had this same problem on several trucks over the years.
It is possible that the connections at the valve cover gasket (which has wires incorporated in it) that could also have a similar problem, but check that 42 pin first.
Good luck, Larry
I have had this same problem on several trucks over the years.
It is possible that the connections at the valve cover gasket (which has wires incorporated in it) that could also have a similar problem, but check that 42 pin first.
Good luck, Larry