glow plug help

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Dec 27, 2010 | 10:32 AM

daleyboy

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glow plug help

I think i have some bad glow plugs. it is very hard to start in the mornings even if its only 40 degrees or so outside. But, if you plug it in, it starts right up like it supposed to. its a 2003 with a 6.0. The question is , if you unplug the plugs on the GPCM .can you test each individual glow plug on the pins in the connector.On my other truck, which is a 85 f250 with a 6.9l, i can clip a test light on the positive post of the battery and with the probe end touch the top of the glow plug. if the light comes on ,the glow plug is good, if not ,its bad..Can i clip the test light on the positive post on the battery and probe the A B C and D pins in the connector that i took off the GPCM and test the individual glow plugs on my 2003 6.0l
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Dec 27, 2010 | 11:03 AM

dchamberlain

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From: Scio, OR

You can test the glow plugs individually. I would not try to use the connectors to the GPCM itself, though. There are other pins there, such as power, communications, etc. There are individual connectors on the left and right buss bars. There are 4 pins each in them. One pin per plug.

However, the GPCM should be monitoring them for you. If a plug is bad, a code should be set. If you can get codes read you should be able to tell if you have any bad plugs.

Dec 27, 2010 | 05:50 PM

daleyboy

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i got a schematic that shows which pins are the ones for the glow plugs, so it should be ok to test them there right?

Dec 27, 2010 | 05:51 PM

gearloose1

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Can you measure current via a clamp on ammeter?

No current = dud.

Dec 27, 2010 | 05:53 PM

dchamberlain

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From: Scio, OR

Quote:

Originally Posted by daleyboy

i got a schematic that shows which pins are the ones for the glow plugs, so it should be ok to test them there right?

As long as you know the pins it shouldn't be a problem. You could simply use a ohmmeter. If you see a short (no resistance at all), or open (infinite resistance) then you'd know you had a bad plug.

Dec 27, 2010 | 07:38 PM

mrwrench

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From: urbana il

I think bad glow plug will turn on the check engine light

Dec 27, 2010 | 09:09 PM

cheezit

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From: N. Fort Worth, tx

2003 moniters gpcm operation but no light. that came later on. 06+ i think.
anyway do not use a test light to check glowplugs on your 6.9 or your 6.0. the theory is good but you can be mislead as to weather a glowplug is good or bad.
as said there are buss bar connectors for each bank test there with a dvom should be abour 2 ohms.
IMO you dont have a just a glowplug issue. if you have a glowplug concern at all.