Wireman:
My D had a similar problem that turned out to be the PCM, or should I say the heat in the engine compartment (eventually) damaged the PCM.
I would get a dash board computer message (displayed in the trip odometer VFD Display) that read: "NO BUS" I could cool down the pcm by pouring water over the heatsink side of the unit (the side of the pcm that is next to the wheel well. That would make it come back to life in about 3-5 minutes. The reason mine was (and maybe yours is too...) completely dead is due to the pcm activating the power control relay that (among otherthings) supplies 12v to the ignition system. I also did a few things to help reduce the under hood temps: a) put in a 180 degree T-Stat b) removed the insulation blanklet from the bottom of the hood. c) removed the rubber air blocking sheets from the front of the unit on the drivers side. Then I put in a powertrain control module from mopar performance. The airflow mods helped the pcm tolerate the under hood heat better, but it would still fail on hot days, hence thew new pcm. Note: I was able to get a moparPerformance pcm insteade of the stock one was that the performance unit was less expensive, not that I ddon't appreciate the performance enhancement. I just wanteded to fix the stall problem once and for all.
I have read that the pcm electronics main cicurcuit board will eventualy develop a microscopic crack from expanding and contracting from all of the times you use the vehicle, so without the airflow mods you may eventually start having the problem again in the future. I will probably add more vents to the engine area if possible and have toyed with the idea of sealing the pcm into the wheel well cavity to isolate it from the engine compartment. Maybe even reduct the air from the aircleaner input to flow over the PCM.
As an interim workaround initially I carried around a 5 gal can of water and soaked the pcm continuously if it stalled. Eventually I started to use a regular size bag of crushed ice from the convenience store that would fit over the top of the pcm while still allowing the hood to close. The ice was a better solution and would last the longest of the two approaches.
There are other cooling enhancements you should enshure you have on your rig that are documented in the technical service papers for the 1999 D, I got them via Alldata. (the tech bullitins) I have seen at least another fifty owners who have had this problem on their rigs, again I am not sure if this is your failure mode or not. Good luck with the final-final resolution either way, I know from personal experience how much of a pain it is to have the vehicle shut down when you are driving down the road, not to mention the hazzard it creates since it also takes away the power steering and power brakes. I got a couple of close calls during my diagnosis time that scared the heck out of me, but I didn't have the luxury of the use of a second vehicle. Best regards, Joe.
Quote:
|
Originally Posted by Wireman3977
This has been going on for the better part of two years, and more frequently now. When the engine reaches "normal opperating tempature" it will randomly just die. Stall right out. No sputtering, no engine lights. Just sudden engine death. After 10-60 min it will start back up, usually with no indication that anything was ever wrong. Followed the advice of many techs and have replaced all of the following:
plugs and wires
crank positioning sensor
cleaned throttle body and replaced ais motor
cleaned fuel tank and replaced fuel filter-pump assy.
battery is new
altenator is working properly
cap and rotor
air filters/pcv valve
Now I am down to what, the PCM? Can I use one from a slavage vehicle? And a mopar tech told me it must be from the same year as mine, why would that matter???
Also what is this I hear about the durango motors being "sludge factories"? Any preventitive measures I should take to avoid premature engine failure on my main family vehicle?
|