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Discussion Starter #1
Howdy i've got a gmc 1997 6.5 turbo that turns over a ton, but doesn't ever fire up. I drive it everyday and it started up just fine this afternoon but just decided it didn't want to about 30 minutes ago.

Any help?
 

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Legennn... wait for it...
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PMD?

Loosen the top piece on the fuel filter just a touch. Fuel should spout forth from the little tube on top when cranked. If it does, I'd bet on your PMD being bad, as fuel is getting that far, but not to the cylinders.
 

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Discussion Starter #4
yup got lots of fuel coming out. Where's the pmd at? is there a way to check and see if it's bad
 

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Legennn... wait for it...
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The PMD is located directly on the Injection Pump. You'll find it by looking down under the intake manifold (get rid of that Turbo Power cover if it's still there) at the front of the engine, driver's side. It's a little black box with a plug going into it. The only way to tell if it's bad is if a new one fixes the problem.

the best way to go about it is to get a new box (Gray Stanadyne is preferred) mounted on a heat sink and relocated to somewhere outside the engine bay where it can better cool itself. I put mine behind the front bumper, just inside of one of the openings. I used this kit on my 95 and just bought a new one for my 98 (since the one in the 95 was shattered in the wreck).

If your hands are small enough, you can unplug the harness from the original PMD without taking the whole intake off. It's all plug-and-play from there. If that doesn't solve the problem, we might be looking at a bad injection pump...
 

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Discussion Starter #6
So i went out late last night just to give it another shot and it fired right up... drove it all day today and probably started it about ten times. seems to be fixed... Maybe i just flooded it when i tried to start it? i was in a hurry and didn't wait for the glow plugs to warm up and thouight giving it some gas would help... i guess i'll justwait to see if she fails to start again.
 

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Discussion Starter #7
I went out just this morning and i'm back where i started again... Is this typical of PMD's to work on and off as they are going bad? You think it's still the pmd?
 

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Legennn... wait for it...
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Very much so. When the PMD on my 95 started failing, it would randomly die, usually as I was driving down the road, just like someone reached over and turned the key off. Starts got harder until it just wouldn't start any more.

After the wreck, I had to plug the original unit back in, since my replacement got destroyed. It ran enough to get the truck from my driveway down to my father-in-law's (he's got air tools, I don't), but after I got the parts off that I needed, it once again wouldn't start. I went back down there after a 2-day road trip for work, and it fired right back up... ran for about 10 minutes, died and wouldn't fire again.

My 98 I just bought had a replacement PMD on it, but I replaced it anyway since it was showing the beginning signs of failing. It wasn't too bad, and when I put it on the 95 when I sold it, the guy who bought it from me actually drove the truck from my place down to my wife's office to load it up on his trailer.

I am 99% positive it's your PMD
 

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Discussion Starter #9
So after i said that, i went back out and drove it to school. Started up every time since.
Hasn't died on me yet... and runs strong when it's running.
 

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x2 on your pmd. we ran about 5 of these 6.5s before we got 2 duramaxes and a 99 cummins.PMD Isolators for GM 96-01 6.5T entire kit for the fix, and these are the best replacements. we've got one that we've run on different trucks for the past 10 years and its still good.
 
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