I have a 2002 Excursion 7.3 diesel. Check engine light came on. Scanner says cylinders 2,4,6,8 glow plugs not working. I think it's the fuse for that bank of plugs. I can't find it. Manual says there is a fusible link, for each bank of plugs, in the wiring harness that leads to the glow plug circuit but nothing else more specific. Can someone please tell me where to look?
Mike

 

i have never seen or head anything that refers to a fusible link in the glow plug system. your X has a glow plug module that monitors the current to each bank of glow plugs. if one or both of the banks shows a lower than normal current it will set a code and direct you to the bank with the low current. i would say you have one or more bad glow plugs on that side.

check this out:http://www.streamload.com/nlemerise/Ford/gpr.pdf

 

I fixed the problem. I found a loose connection. thanks

 

where was the loose connection?

 

Help me out here,
Where was that loose connection - I have the 2,4,6,8 glow plug circuit error, and the Fusible Link (Yes, there is one for each side) does not seem to be the problem. I'm looking for a loose / lost connection somewhere and haven't found it yet. It is doubtful that 4 glow plugs failed at the same time.

Please advise - ideas welcome.
Thanks!

 

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I would suspect it was something simple because he seems to have found it quickly. Would have been nice if he had said what it was but I suspect it's somewhere between the gpr and the harness at the offending head. He may have pushed/pulled his way right into identifying the problem. Good luck and let us know.

 

i wonder if the fusible link is an "excursion/california truck" thing...anyhow like i said in the other post the PCM only reads the current for the entire bank and if its low it sets a code for that bank (left/right) there are not sensors for each glow plug. if just one was bad it would read low current for that bank and set a code. you know generally where the problem is, now you have to find it. bad GP, chaffed or burnt wire/harness under the valve cover, lose valve cover plug...

i would guess the lose connection he is talking about is the VC (valve cover) plug. it is on the top middle of each valve cover

 

Thanks for the input - I've checked and re-checked that connector on the head- will keep searching and let you know.
Regarding the fusible link(s), they are on all non-CA motors on the GPR, at least in the Excursions....I would not have found it except for a reference in the Haynes manual.

Regarding errors, I am getting 4 separate error codes: one for each individual glow plug. The quick response from the parts store was to sell me 4 glow plugs, however, I'd heard a few people finding loose / missing connectors,etc.
Here are the errors specifically that I am getting:
P0672,P0674,P0676,P0678
On my previous daily driver - '97 Ford Expedition, I did get the code errors for the entire 'bank', and not cylinder by cylinder..
it's nice that the 7.3l will actually (hypothetically) display an individual GP circuit fault, helping to diagnose it directly.

In any case - thanks to all for the input - I'll post the solution when I find it, and appreciate all further ideas / experience, etc.

next up - pulling the valve cover and checking the connections at the GPs and internal connector. . .

 

Hmm, I'm sure someone else will chime in but I just can't see a whole bank failing all at once. You can check the circuit at the GPR and then the harness with a meter to at least verify the need to pull the valve cover. Is it starting OK? If so, have the trouble codes reset after verifying the juice at the valve cover connector and GPR. See if it returns.

On edit: as for the fusible links, I don't have/know about them. Run a jumper of sufficient gauge and bypass it, after resetting the codes and see if it returns.

 

I'm having the same code and SES light. Any results from the above people?

 

Ditto, Service Engine Light is on, codes from Autozone P0672,P0674,P0676,P0678

If anyone has any input on where to look, I'll take it, otherwise I'll follow up once i trace some wires and see what I can find...

 

It is in the harness Near the GPR there are 2 12ga gray wires. PM me your email and I can send you the schematic. It doesnt locate them avery well but will get you in the area and let you know what to look for.

 

Same thing happened to me, 2001 Excursion, same codes as well referenced above, all four even numbered cylinders. I ended up taking to a Ford dealer and they diagnosed as a bad GPCM, replaced it and a few hundred bucks later, no more check engine light. Just fyi...

 

I am guessing that you are going to need to do a resistance check from ground to the different Glow plugs, but I am thinking that your problem is going to be the valvecover gasket, am I wrong here, that is the only harness I can think of???? If you can look in this thread for glow plug wiring, someone posted it about a week ago I think..