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PMD issues? 1996 K1500 Suburban I have a 1996 K1500 Suburban. I've had 3 bad Gray St

jrsavoie

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If this thread is in the wrong spot, please move it or delete it. Couldn't decide between here or electrical.

PMD issues? On the 1996 K1500 6.5 diesel Suburban

I have several 6.5's

I've had 3 bad Gray Standynes now - if this is a PMD issue. I'm not sure of this last one yet. The 1996 Suburban is dying and restarting like it is having a PMD issue.

The gray PMD was installed sometime in 3 -2013. No idea when I bought it. What gives me pause is that I plugged into the spare and it did the same thing.

Both Ran for about an hour, died, cooled down and restarted, ran for another 1/2 hour, died, cooled down and restarted.

I have not tried a known to be good PMD yet. The truck was gone before I could get the known to be good spare off of it to put on the Suburban.

I have a new PMD ordered from leroydiesel.com

Any thoughts on what it might be if the next PMD does not work?
 
I would check:
1.) Pull codes from ECM.
2.) All grounds to block & IP/PMD-FSD.
3.) I can't remember which pins, but using a DMM verify Ohms of the pump's Fuel Solenoid from PMD-FSD side of harness. If yours is remote located this should be rather easy!

Note: For a while now I’ve been suspecting that the windings of the pump’s F-Sol break down due to vibration and heat. This condition could be accumulative, and /or intermittent. As more windings rub through their enamel, the soft-short becomes worse. This reduction of resistance would draw over spec currents through the PMD-FSD, and as we all know too much current draw is bad mojo to electronics.

4.) Verify voltage at Battery & Alternator at cold & hot idle. Cold should be >13 - <15VDC, hot should be >12.8 - <14.5Vdc. If voltages are out of whack PDM-FSD will suffer.
5.) Inspect as much of the Harness to PMD-FSD, unfortunately this will most likely require the Manifold to be pulled.
6.) What in the way of non-OEM electronics are installed on the vehicle, IE stereos, amplifiers, CB radios, Etc. Many of these devices have switch-mode pwr supplies that can induce high Fq’s on the 12v of the vehicle. The PMD-FSD is basically a current amplifier, as such, it may be susceptible to common mode and high Fq noise. This could cause an oscillation feedback loop in the module, drawing excessive current and operating at above spec temps until it’s premature failure?

Just some thoughts on these modules!
Good Luck, one owner with three failed "bulletproof" units doesn't sound normal - they haven't been out that long!:thinking:
 
I would check:
1.) Pull codes from ECM.
2.) All grounds to block & IP/PMD-FSD.
3.) I can't remember which pins, but using a DMM verify Ohms of the pump's Fuel Solenoid from PMD-FSD side of harness. If yours is remote located this should be rather easy!

Note: For a while now I’ve been suspecting that the windings of the pump’s F-Sol break down due to vibration and heat. This condition could be accumulative, and /or intermittent. As more windings rub through their enamel, the soft-short becomes worse. This reduction of resistance would draw over spec currents through the PMD-FSD, and as we all know too much current draw is bad mojo to electronics.

4.) Verify voltage at Battery & Alternator at cold & hot idle. Cold should be >13 - <15VDC, hot should be >12.8 - <14.5Vdc. If voltages are out of whack PDM-FSD will suffer.
5.) Inspect as much of the Harness to PMD-FSD, unfortunately this will most likely require the Manifold to be pulled.
6.) What in the way of non-OEM electronics are installed on the vehicle, IE stereos, amplifiers, CB radios, Etc. Many of these devices have switch-mode pwr supplies that can induce high Fq’s on the 12v of the vehicle. The PMD-FSD is basically a current amplifier, as such, it may be susceptible to common mode and high Fq noise. This could cause an oscillation feedback loop in the module, drawing excessive current and operating at above spec temps until it’s premature failure?

Just some thoughts on these modules!
Good Luck, one owner with three failed "bulletproof" units doesn't sound normal - they haven't been out that long!:thinking:


The Gray PMD's were on various vehicles. I haven't been keeping the records as tight as I used to. I do not remember which were which. No electrical add on's here.
 
I tried a 3rd PMD. It did exactly the same as the first 2. One of which I think was a new gray PMD. The other was 9 months old.

The 3rd PMD was a black Standyne that I had. It was mounted on a heat sink and had OK written on it.

I haven't been able to have the truck here to check a known to be good PMD. I am leaning towards thinking it is the injection pump.

What is a good price for an injection pump, installed? Pump and installation? Anybody within a couple hundred miles want a side job?

The 1996 K1500 Suburban runs for about 2 hours and then dies. After it cools down it restarts normally. There is NO check engine light and I could not get it anywhere to check for codes.

I was given a price of 1200 to 1300 for an injection pump installed. With the weather, doing it here in my shop is not an option. The 1998 Suburban still needs a transmission. Again I'm dealing with bad weather and an unheated shop.

I'm usually not much for throwing parts at things, I'm reasonably sure that it is not the PMD's. I tried 3 and they all did the exact same thing. Ran for 2 hours and then the Suburban dies. It also seems to take longer to cool down to restart than PMD's usually do.

Any opinions would be appreciated.
 
Have you ever thought to get one of those bullet heaters? They run on kerosene, seen some lately that run on propane. Put the truck in the shop, fire the heater up facing you. Nice and toasty! Just would have to leave the door cracked for ventilation. Here is what I am talking about.

http://www.tractorsupply.com/en/store/masterreg;-kerosene-diesel-forced-air-heater-135000-btu

I just learned they are also called force air heaters. Here is one locally for $60

http://killeen.craigslist.org/grd/4232952764.html
 
Val 6 from our local agco dealer.

enepu6y3.jpg


Heats a 120x80 insulated shop to 60.

Source Unknown
 
jeff, after reading the thread, have you checked for fuel delivery? snotty sock, vaccum, etc?

connection on shut off solenoid? THe DS4 is shut down by the computer killing the fuel solenoid, but also by the FSOS, correct? could it be possible the solenoid is getting weak and closes when hot?

Just a WAG, but some things to check before condemning the whole pump.

good luck!
 
Will do. Hopefully will work on it again tomorrow. I think I have a new fuel shut off solenoid in the counsel of one of the vehicles. Probably which ever one is not here at the moment.
Thanks.

There wouldn't be much worse than changing the IP and still having the same problem
 
Val 6 from our local agco dealer.

enepu6y3.jpg


Heats a 120x80 insulated shop to 60.

Source Unknown

What does one of those run? How much fuel does it burn in 8 hours or so?

I think one of these heaters would work: http://www.northerntool.com/shop/tools/product_200596883_200596883

EcoBlaze Indirect Portable Kerosene/Diesel Heater — 1,760,000 BTU, 16,000 CFM, Model# Blaze 2000 D
Only $48,99999

I don't want to/can't afford to invest to heavily in a heater when I plan on insulating and installing a floor next year.

Those Val 6's look nice but the price I saw was over 2 grand. That'll buy a lot of concrete and insulation.
 
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