After a few years of 6.5's in 2 trucks I have found the PMD can cause some strange things to happen.
The worst is it just kills the engine, but there are many other things I have traced back to a PMD that I thought I would share.


1/ Runaway throttle while driving. This is exciting, and it required the key to be turned off to stop it. Replaced PMD and all is well

2/ Surging throttle at idle in park. needed to shut off key to stop it. Replaced PMD and all is normal again

3/ sudden loss of power, I think they call it limp mode? Replace PMD and all is well

4/ cruise control fails to work. ?? replace PMD and all is fine.

5/ Oil pressure gage drops to zero when brakes are applied. Even while completely stopped and foot on brake makes oil pressure show zero. Take foot from brake and pressure reads normal. replace PMD and all is well again.??

6/ Truck dies . Starts right up again and dies . Replace PMD and it runs fine.

I have 2 PMD's mounted on each truck and now the first thing I do when something is not right is plug in the second PMD to see if it fixes the problem before looking elsewhere. More often than not it is a PMD starting to die.

It isn't always the PMD causing troubles, but it does seem to be able to cause grief in things we wouldn't think possible , like the OP gage and cruise control. Now it seems like the first thing to do whenever something acts up is switch the PMD plug to the spare and see if it fixes the issues before chasing grounds , wires and fuel supply issues..

I am curious what other things some of you have traced back to a faulty PMD?