My money is on a bad OPS (oil pressure switch). This switch fails often on these trucks and if it isn't working the fuel lift pump will NOT turn on. 6.5's can run with a non-working fuel lift pump, but they are hard to start, they will die randomly, and they will surge at hugh RPM's etc.. This is often mistaken for a failing PMD/FSD. The OPS is located on the rearmost portion of the intake manifold on the drivers side.
Andrew
How about an update, is it fixed, or?
Well, back to square one. it does not run again. it started but then shut off after a few seconds.
A question - if there was air in the system, shouldn't it keep running once it's started? I am starting to suspect something else is wrong with it.
let me re-read this thread again.
All right I took a quick look - there is fuel coming out the fuel filter at the back of the engine.
there is also a ODBC error code - P0126 Coolant Sensor
I am going to go ahead and order the FSD, looks like it would be good anyway to replace it.
All right guys - thanks everyone for your input.
it turned out to be....
...
..
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the PMD/FSD - the electronic module attached to the fuel pump. I got another one with an extension cable, dig around for an hour to find the existing one and unplug the cable, plug the new one and voila!! Started right away.
thanks again everyone. Now I just need to see if this ODBC code is still present.