Thank you so much for the reply. I realized i get the glow plug light if i have the batteries fully charged.. havent had enough time to see if the glow light is acting up still.

I got the truck for free from a friend and they said it turned off like the key was turned and would crank and not restart.

It also had an alarm that i removed. I was unable to find any cut wires to disable it from starting... i checked under the dash and by the ecu.. its just another thing to add to the mix.

Thank you so much. Im trying to get the truck running ASAP so ill be updating this thread often.


Whats the average real world MPG on these trucks in proper running order?

 

I ave 18ish... lil more interstate, lil less in town..
20mpg isnt unheard of either...

 

Hey can someone help me on my truck , I have a thread already but no one has replied yet ,, need help from one who really knows what they are doing and this 95 6.5 td truck

 

Try reconnecting the alarm or look into a alarm system just like to , look in the instructions it should tell you how it's wired and what exactly it's wired and tied into , it sounds like the alarm system is tied into the ecm or pmd power or could just be a burnt out pmd iv noticed that gm made these truck very complicated and poorly designed , and ran circuits in pair with other circuits. So even tho you may not see anything cut worth it being vital to the truck running or not , you'd be surprised .

 

So I got around to putting a little time in on the truck..


As a recap..

The glow plug circuit is my main concern. As previously stated the glow plug circuit has negative 12.5 volts, so something is up. The ecu wont power up and the dash lights sometimes come on and dont.. it will crank but not start. The truck had an alarm that i removed when it wouldnt start, 2 relays and a fuse were removed, no wires were cut on the alarm install so im keeping it in mind that the relays could very well have controlled something. Ill ask the ex owner (friend) if the alarm was wired to control the engine.. They said it turned off like the key was turned.


Recently I disconnected the 2 wire 3 prong connector by the filter housing, pretty sure this was the fuel heater, i need to verify. I also unplugged the glow plug controller and i still got the same reading of -12.5 volts on the circuit that is supposed to be positive (im pretty positive.

Ill check to make sure i disconnected the right plug for the fuel heater, but im becoming clueless why i would get negative on the glow plug circuit even if it was the alarm cutting it off, unless it has something to do with the crazy electrical system these trucks have.


Thank you guys! Im itching to have this thing running!

PS. The alarm would take some work to hook back up, but if this looks like a possibility, let me know

 

batteries connected backwards or charged backwards?
leads reversed on the multi meter?

 

The batteries are charged correctly and the other circuits test out normally so im pretty sure something is grounded out.

Ill verify that i do in fact have the fuel heater unplugged then disconnect anything on that circuit and see if anything changes. Any other ideas?

 

I have pretty much the same problem you'll be driving an it'll randomally stall like you shut the key off when an when you go to restart it I noticed the service throttle soon light would not light up an the glow plug light wouldn't light but if i let it sit for a few hours it'll sometimes start an run normal if it's not hot out but on a hot 80° degree day won't start at all I've replaced the PMD remounted it behind the bumper replaced the ECM replaced the ignition replaced the glow plug controller an im at a loss im so ready to scrap the damn thing it's a money pit an I still can't figure it out :/ mines a 94 k2500

 

To everyone except OP (original poster aka schmauster) needing help. Please start your own threads so theres NO CONFUSION. Someone will be along to help you shortly, if they can..


Engine just shuts off as if a ghost had switched the ignition OFF..

Start with the Important Preliminary Checks, followed by OBD System Check for any DTC(s), followed by a lengthy series of monotonous Fuel Supply System Checks.

ANYTHING that disrupts the Optical Sensors relaxing day at the diesel spa will alert the PCM. If the PCM remotely feels threatened or remotely suspects catastrphic damage is imminent, the PCM shuts EVERYTHING down just as if a ghost turned off the ignition.. When the PCM hits the panic button, entire system shuts down and appears dead because nothings communicating. PCM's posum play can last as long as 20 seconds while it reboots and gathers its senses. If the condition still exist when the PCM reboots, it can immediately default and/or just hit the panic button again and again or until the condition no longer exist. Grind the starter (crank the engine) all you like, dont matter. Engine will not start until the PCM says so. Often this condition is ROUTINELY misdiagnosed as faulty IP, defective PCM or failing PMD.

Dont skip the "Important Preliminary Checks" and dont simply go through the motions, be excruciatingly THOROUGH!!

Dont forget to check the last ditch screen..


Air is the EFI 6.5TD Kryptonite.
Grungy Grounds, its Nemesis..




Ive attached a pic of the FFM. Should help you to identify the Fuel Heater which has 2 wires whereas the WIF sensor has 3.

The fuel heater's element are known to short out internally.

 

Had to hunt for your thread, found it in the tech review.?.? Maybe a mod can move it to the appropriate forum... Until then, heres a link.
No Glow Plug, No Start