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Where's Goldsberg ?

Didn't give it a chance. I have 235k on this engine and it needs to go at least another 50K before I replace it.

Was running with the cruise on, kicked the brake to slow down and the truck never lost speed. Then I turned the cruise OFF at the switch and never lost speed. I then clutched it and put the trans in N. The truck then started gaining speed.

I then shut it off and pulled off the road. After opening the hood and check all of the connections to the remote PMD and cable (good), I then started it up again. After a few seconds of somewhat rough idle, the engine slowly took off again. I called AAA for a tow.

Living in one state and working in another (on the weekends), I didn't have time for more in depth diagnostics, so I had it dropped at my local mechanic who is 6.5 diesel competent. That was last Saturday. I explained the situation and he said he had a plan for diagnostics, but was going to call me Wednesday with the results.

So he called yesterday and said that he drove the truck for 20 minutes up and down the country roads around his shop, at various speeds and loads, and could not reproduce the problem. He put his scan tool (make unknown) on the ECU and could not find any codes, which is not surprising as there was no MIL during all of this. Everything else checks out: fuel level, fuel pressure, fuel filter, newer injectors (from Tim at Accurate). The best that I am left with is that I have a malfunctioning DTech remote PMD. I intend to replace it soon and need to make a decision about what to put in its place. The one thing that I am SURE of is that I will be using a heat transfer compound this time instead of the heat transfer pad. This was a suggestion from Tim at Accurate as possibly the only "base" I didn't cover when making my remote PMD cooler assembly.

Regards,
 
Having worked with many computer electronics components, the heat pads are crap in comparison to a thermal compound. When you take it apart see if there is any corrosion in there and under the transistor covers. Or if the transistor nuts are loose.
 
Great to see you . Too many senior members MIA. FWIW I have a dtech remote mounted from Leroy and I used Arctic silver on it and I could swear one time the throttle didn't let off but i thought I was nuts. Now you got me thinking.......
 
Good to hear from you Goldsburg, during my lurking at the page/place/DTR I have always enjoyed reading your thoughtfull posts.

I must admit I had to chuckle at the recent thread started by the newbie guy that had the PMD lawsuit website etc. During that thread it obviously came up that he was wasting his time and IIRC that there was no known serious vehicle accident issues from a PMD failure. Well my failure on a stanadyne was like Golds a runaway condition and I would submit that a panicky style driver in my situation may very well of hit the car in front. In busy traffic as I was leaving a corner I began to accelerate when sure enough the revs shot up she dropped down a gear and went flying towards the car in front, luckily there was enough of a hard shoulder that whilst shifting to neutral and braking I was able to steer alongside the car in front at which point she stalled out. Granted it would not of been a serious collision which is why at the time of the prior thread I kept my trap shut, however it does make me ponder if there are indeed any PMD failure related collisions out there.

Cheers
Nobby
 
Seem to be increase in reports of pmd failures on this & the other site ,both stanadynes new & improved & flight systems ,runaways I believe, but no spectacular crashes reported.
 
Seems odd how a runaway would occur from a PMD. The IP has to close the fuel solenoid to start injection, PMD has to provide power to open it, then take power away to close it. This almost square wave pulse has a higher duty cycle for longer pulse width to increase fuel output to increase RPMs. How it manages to fail in a manner that still has a sqaure wave is odd. Unless the voltage of that wave matters. At idle the wave is not quite 2V, and at 4000rpm its about 5V, but the duty cycle or pulse width would seem to be the most important part, or is amplitude also important, and the PMD is cranking up the voltage output even at low pulse width. The pulse widths are short, 1.5-2.5 milliseconds so I guess that too can be sensitive to just a bit of delay of the transistor hanging onto the voltage causing a wider pulse width.
 
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