mind boogled (glow plugs?)

Bigford0707

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how can you tell if your glow plugs are bad? my truck is a 2001 7.3, 30 degrees and below, it is very hard to start, is there a way i can test the glow plugs?
 

Tail_Gunner

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If you disconnect the harness connector that goes under the valve cover, IIRC the outer two wires on each end are the glow plugs power leads. If you use a OHM meter, you can check for continuity to ground thru the glow plug, it'll tell you if that glow plug is bad or not. When they go bad, they usually burn out like when a light bulb goes bad. If you do not get a continiuty reading (i.e. an open circuit indication), that'll indicate either a bad glow plug or a disconnected or an open wire. Replacing glow plugs is not that hard, just more like a PITA, especially if it cold outside and you're doing it in the driveway.:innocent Just say a prayer beforehand that all of the glow plugs come out and the tips don't break off and stay stuck in the hole. I've heard of that happening, just not to me. Don't ask what you do in that case, you won't like the answer.
But first, I'd check that the glow plug power relay is sending power to them. A relay is a much easier fix than glow plugs are.
 
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rammertide07

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I'd check the relay first (burnt spots....good connection). If thats good, then you have to cycle the key over for the WTS light to come on. Just because the light goes off doesn't mean that the relay is not getting any juice. Check it with a volt meter, I think you got 1-1.5min to check it. If it is getting juice then the only other thing I can think of is to replace ALL the glow plugs.

Also may want to make sure your batt's put out enough CCA. I think mine is around 900:dunno

I know I didn't cover it all (name brand glow plugs...specifics??) Someone else will chime in
 

early 99 stroker

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Pin Out for the 9 pin plug at the valve cover

G G I I C I I G G

G=Glow Plug +
I = Injector +
C= Injector Common

***The injectors fire with a 115VDC signal from the IDM do not pierce to wires to test.***

Ohm between "I" and "C" to test the injectors, should be less than 5.0 Ohms

To check glow plugs Ohm between "G" and battery ground should be between 0.1 and 2.0 Ohms
 

Bigford0707

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glow plugs

man you guys now these trucks!!!! hopefully i can test before the weekend, the truck is not my daily driver, so when i do try to start it, it works real hard to get started, and most of the time below 30 degrees i have to plug it in. So when by buddies can start there cummins at damn near zero degrees, And when if mine sits for two days in the 20 degree mark i cant get it started or barely fire on one cylinder and it will surge till it dies out, (acting like maybe there is a faulty glow plug). Well i keep you guys updated. I love my 7.3 and it might not be the fastest or have the most torgue, but these things are one tough diesel engine
 

JLDickmon

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So when by buddies can start there cummins at damn near zero degrees, And when if mine sits for two days in the 20 degree mark i cant get it started or barely fire on one cylinder

differences in the design of the cylinder head.
 

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