Check Engine Light/ Engine Runs Rough

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Oct 31, 2007 | 01:08 PM

lud04X

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From: Richland, WA

Check Engine Light/ Engine Runs Rough

I just got done checking the glow plugs and I know I need to replace 4 of them as they are bad. I'm going to get all 8 replaced while I'm at it.

Anyway I put everything back together or the time being and drove the truck home from my buddy's shop. When I got halfway home the CEL came on and I lost a lot of power and barely made it home. As soon as I stopped the light went off and the truck was fine. I started it up and couldn't repeat the problem. The problem seemed intermittent.

Drove it a few times with no problems. I drove it over to my buddy's shop last night and about halfway there I lost power again, felt like the truck was running on 4 cyliders. Got my buddy's scanner on it. It says injectors for cylinders for 5 and 6 weren't working. I think maybe I left something loose after disconnecting the connectors to check the glow plugs. I checked and all the connections are ok.

Anyone have an idea of where to go from here? I'm stumped as I believe cylinders 5 and 6 are on opposite sides of the engine. So unless I have two wiring harnesses that are messed up I believe its the injectors.

How much do injectors cost?

Oct 31, 2007 | 01:18 PM

tjbeggs

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From: Silver Lake Dunes, MI

could be loose connection but as you said 5 and 6 are opposite sides. also could be a chaffed wire on the main engine harness. look at it where it doesn't have wire loom on it and look for wires that have the insulation rubbed off.

Oct 31, 2007 | 01:41 PM

lud04X

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From: Richland, WA

Where is the main engine harness? I think its kinda weird this never happened until I took the connectors apart to test the glow plugs. I think its a pretty good coincidence that this is when I started having injector problems except that the injectors are on two different sides. Maybe I just have 2 loose connectors?

Oct 31, 2007 | 01:53 PM

tjbeggs

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From: Silver Lake Dunes, MI

The main harness comes over the driverside valve cover. its about an inch in diameter.

Oct 31, 2007 | 01:57 PM

Cuda_jim

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From: MICHIGAN

Maybe the pins were pushed in when you reconnected the UVC's. It was running OK until you 'fixed' it...right? The connectors are delicate after 10+ years of heat, oil and fuel getting to them. The little pin keepers can break fairly easy. My .02

Nov 1, 2007 | 11:46 AM

lud04X

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From: Richland, WA

Got the valve covers off. I found 2 bad harnesses. The one for cylinder 5 was melted. The harness for cylinder 6 was also bad. That would cause my orginal problem. Got a friend who works at Ford to get me the parts. I'm also gonna get two valve cover gaskets as well. I'll let you guys know how it goes.

Should I replace all the harnesses while I'm at it? The other ones look fine and weren't giving me any codes or problems.

Last edited by lud04X; Nov 1, 2007 at 11:49 AM.

Nov 1, 2007 | 11:57 AM

plowhand

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From: Southwest Georgia

If it was me, while I have it open, I'd replace all of them. That way everything is new and you don't have to worry about when the other two old ones are going to fail. Plus you'd have to tear it back apart later when the other two fail. 10+ year old wires.