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Old 6.5-T strikes again !

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I am working at home limited toolage on the car trailer in the street !

You know when this is all done and the truck runs again ill be right back to complainting about its major lack of power...

I am still all for get a nice BBC n being done with all of this nightmare crap !

Mikey
 
ok that stupid fuel solenoid is finally plugged back in. . .tho i cheated i tore the top of the intake off the SOB to get a better grip on it. . .

Now to see if i can find a bloody wrench and crack the injector line, and see if it shoots fuel all over the place. . .

( your sure a 454 wouldn't be better ?) :thumbsup: :D

Back to it. . .

Mikey
 
Injector had some fuel in it where the line connects but the line itself was dry. . . spun the engine over several times not so more as a drop came out of the line. . .

Now what ?

Mikey
 
Try a different PMD - if you still have the original one mounted on the IP , you can try that one, since it's just a matter of disconnecting the extension cable and hooking the original one back up. Did you grab a multimeter and try measuring the voltage at the PMD connector like Buddy suggests?
 
Check the ecm fuse in the engine compartment fuse block, shine it up and reinstall it. A known good PMD would also be handy for diagnosing.

Leo
 
Check the ecm fuse in the engine compartment fuse block, shine it up and reinstall it. A known good PMD would also be handy for diagnosing.

Leo

Fuse box has been checked 3 times all fuse were fine contacts where cleaned up. . . along with every body ground i could see. . .

Try a different PMD - if you still have the original one mounted on the IP , you can try that one, since it's just a matter of disconnecting the extension cable and hooking the original one back up. Did you grab a multimeter and try measuring the voltage at the PMD connector like Buddy suggests?

I don't have a multimeter handy nor do i have wheels to go get one. . .PMD on the IP . . . :eek: :mad2: No way can i get in there to plug it in. . .:thumbsup:

Mikey
 
I don't have a multimeter handy nor do i have wheels to go get one. . .PMD on the IP . . . :eek: :mad2: No way can i get in there to plug it in. . .:thumbsup:

Mikey

I didn't say it was easy, but it can be done... might be easier to unplug the extension from the PMD behind the bumper and route it up there, it'll give you a little more slack to work with.

If we are able to UNPLUG the things in order to install the extension, we can plug them back in. Need needle-nose pliers and a little patience.
 
Oh yes if i had bought your fancy $40 extension it would be a simple unplug replug. . .
But i didn't i took the stock GM cable cut it in half and took a roll of wire and made it longer !
there is no way to get in there with 6ft of extra wire, nor am i going to try to. . .

Mikey
 
First off the get the wires unhooked i would have to unbolt the PMD/FSD from the bumper. . . then rip the top of the intake off one more time today then struggle yell scream n throw stuff till i got it plugged into the JUNK PMD in the IP. . .
Not worth it to me. . .

by this time next week that 6.5 will be rippons of steal in a container ship heading for china. . .next year it'll be body panels of a new toyota. . .


Mikey
 
Without any multimeter its a toss up of completely dead PMD or flaky extension harness.

I'd order a new PMD, not too bad at $163 at pensacola diesel website. What amazes me is they will sell you an intake mount setup for $274 but with a 6' extension is only $5 more. You already have heatsink and extension though so dont need it the kit.

In the mean time while you wait, you could pull the PMD you have off, pop the transistor caps off see if the transistor nuts are loose, tighten them finger tight, and then a smidge more, 1/4 turn. Leave the caps off, thier not needed. Mount it or not, plug that right back into the extension and see if it will start. If you didnt mount it and it starts, put it back on the heatsink with some thermal grease and hope it lasts a few weeks or whenever you can get a new one.

It always comes back to the original problem doesnt it? Its so annoying beause the same thing happened to me but with another part and you thought you had it fixed.

A flaky PMD can also cause it to be underpowered. You might check what resistor value is inside your PMD connector, its a little Printed Circuit board the shape of the connector that sits at the back. When ordering a new PMD you can increase power a little with a #9 resistor (ordered separately $26) if you have a #5 now. A higher resistance increases the fuel output above what the PCM commands. Or at your risk could put in a $5 potentiometer across a couple of the lines and dial in your own resistance until it throws codes.
 
Without any multimeter its a toss up of completely dead PMD or flaky extension harness.

I'd order a new PMD, not too bad at $163 at pensacola diesel website. What amazes me is they will sell you an intake mount setup for $274 but with a 6' extension is only $5 more. You already have heatsink and extension though so dont need it the kit.

In the mean time while you wait, you could pull the PMD you have off, pop the transistor caps off see if the transistor nuts are loose, tighten them finger tight, and then a smidge more, 1/4 turn. Leave the caps off, thier not needed. Mount it or not, plug that right back into the extension and see if it will start. If you didnt mount it and it starts, put it back on the heatsink with some thermal grease and hope it lasts a few weeks or whenever you can get a new one.

It always comes back to the original problem doesnt it? Its so annoying beause the same thing happened to me but with another part and you thought you had it fixed.

A flaky PMD can also cause it to be underpowered. You might check what resistor value is inside your PMD connector, its a little Printed Circuit board the shape of the connector that sits at the back. When ordering a new PMD you can increase power a little with a #9 resistor (ordered separately $26) if you have a #5 now. A higher resistance increases the fuel output above what the PCM commands. Or at your risk could put in a $5 potentiometer across a couple of the lines and dial in your own resistance until it throws codes.

Or

I could yank this engine out that i don't understand send it to its grave and drop in a motor I do understand !
I bet this would end the trouble all together. . .

Remove 1 boat anchor install 1 obsolete Relic and move on

Mikey
 
Yeah, this is not the advertised powerful, reliable, diesel you think of when you hear turbo diesel truck. But then again neither were the Dmaxx's when they came out with all the injector and fuel filter and intake and emissions issues they went through to get to the monsters they are now.

Carb'd Gassers are easier when thats what you know, but that doesnt mean the 6.5TD is difficult when you figure it out, and with a little investment aren't all that weak. Just reading through the factory manual shed quite a bit of light on them for me. And researching the PCM and EPROMs and how they are programmed and how to modify it makes the rest seem simple.
 
I find it useless to get to know the GM 6.5's why bother ?
you'll never own a second one ?
there only going to get older n fewer in number, and I don't see this becoming a sought after popular motor folks will track down such as the 265 283 327 350 400 402 409 427 454 502 637 ECT. . .

even if this fired right up and never ever broke once and lived another 250k miles wouldn't ever buy another one. . .
Because of the issues i have had with this one sure i'd know how to fix yea. . .but you see i hate having to fix stuff. . .
In this case a carb'd 454 would be simple and easy tho idealy an EFI 454 would give the best performance. . .

Mikey
 
Its highly sought out by the Army :) Their still using them in their latest and greatest monster vehicles for troop transports. So for many years as real Humvees are sought out they will have the latest in 6.5TD technology.
 
Yea you hasve me there they still have every part of my Mil-spec 53' REO-331 I-6 Gasser in my 2.5 ton 6x6 they even come out with new things for it from time to time. . .
So yea i guess the 6.5 Mil-spec unit will be around for a while yet if there still making stuff for 50+ year trucks the 10+'s got a long ways to go. . .

Fine i'll try n plug in the other PMD but i am almost certain its junk or the second wouldn't have been installed. . .


Mikey
 
True the one on the IP probably is junk, youre right. Although you never know, might just prove the one in the bumper is broke. The one on the IP may be good enough to start the truck, but was replaced because it caused all kinds of stalling.

I wouldnt recommend driving far with the one on the IP, and I dont think anyone was.
 
ARG ! wiring is just fine. . . Truck tries to fire on the bumper mounted PMD. . . it's just fine the IP ain't shooting fuel cause its JUNK but for some reason your not wanting to hear that. . .yes i know PMD's cause good IP's to get replaced but i am telling you the PMD is good and the IP is junk this time i swear. . .

Mikey
 
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I don't think you are taking advice seriously, and now you are tripping over your own foolishness.

Are you sure you didn't do a butcher/hack job extending your own harness?

You never even bought a new PMD just moved / rewired an already dead PMD?

Can't buy a 10 dollar Fuel pressure guage?

Can't find/ borrow / use a Multimeter to do diagnostics?

You should go back to carberated gassers.

If you honestly did with 100% intent without cutting corners at all, and followed the advice given here, your truck would be runnign without flaw.

People tell you what to check, but since you don't get the most simple of all diagnostic tools, you can't.
 
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