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6.0L Power Stroke Diesel 2003 - 2007 F250, F350 pickup and F350+ Cab Chassis, 2003 - 2005 Excursion and 2003 - 2009 van

Cold start issues

Old Jan 29, 2017 | 05:00 PM
  #16  
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original dtc p678
 
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Old Jan 29, 2017 | 06:29 PM
  #17  
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Glow plug code.
 
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Old Feb 1, 2017 | 07:32 PM
  #18  
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ok glad i didnt drive to airport got a ride came home 30f out would not start. this truck has never done this. How do you test the glow plug relay. I do hear all the clicking when I turn the key. It fires wants to start but does not? the only other codes was a egr forgot the which one? All 8 glow plug were replaced did not help it?
 
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Old Feb 1, 2017 | 10:38 PM
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Does it start if you plug it in? The best thing you could do is get ForScan and run a glowplug system test that will give you an idea of what's going on. If you get codes for x-amount of glowplugs then you may need a GPCM.
 
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Old Feb 1, 2017 | 10:55 PM
  #20  
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yes it starts when plugged in
 
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Old Feb 1, 2017 | 11:06 PM
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Maybe someone has the pinout procedure so you can ohm things out just to check the wiring and for power before you spend the money on a module. But if the glowplugs are new and the wiring fully seated it's most likely the module. It's 180.00 gamble without checking those things out first.
 
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Old Feb 2, 2017 | 12:01 PM
  #22  
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P0678 - #8 glow plug circuit - HOWEVER frequently the code for the #8 glow plug circuit really means the GPCM as others have indicated.

You can disconnect the glow plug harness and test the resistance. The harness should read 0 to 1 ohm resistance.

The red wire on the black GPCM connector is the circuit for the #8 glow plug. Each plug should read 0.1 to 2 ohms resistance. If that is ok (and it should be since it is new), then you PROBABLY need a module (again as the others are telling you).

A frequent GPCM problem indicator is low idle rpms if/after it starts (say around 450 rpm).
 
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Old Feb 3, 2017 | 09:53 AM
  #23  
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We seem to have a few GPCM issues during the last 6 months.
 
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Old Feb 5, 2017 | 08:23 PM
  #24  
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Replaced glow pug relay seems to start better but have tried it below 28F however I noticed oil on my blue boot to the intercooler, there should not be oil in intercooler? I did break a turbo shaft and ingested alot of oil but that was 25K miles ago.
 
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Old Feb 6, 2017 | 07:48 AM
  #25  
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Crank case ventilation, oil in the boots is pretty normal.
 
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