06 No start

[waywardtravel]

I am going to be helping a friend out on Monday.
The truck had a nasty knock for a couple seconds when he was about to shut down one day.
He had a charging problem and changed his alternator at that time.
After the alternator swap he started it and idled for about 20 minutes problem free while connected to a scanner doing diagnostic checks.

Then the next day went to start and no start but cranked fine.
He started it on either and it idled good for about 20 seconds to a minute then just died.

It now does not start. I assume it will on either still.

I don't know powerstrokes but do work on diesels just bigger ones and Cummins trucks.
I'll obviously be reading a lot to understand the basics but any obvious things based on that?
I'm going to read and try to find what fittings are necessary and procedures to do the air tests I've been reading about people ruling out and where the oil pressure taps are etc.

 

[6.0 Tech]

Check base oil flow. Pull the oil filter and press down the little black check valve in th bottom with a long screw driver. Have someone crank it over using the starter signal wire by the battery so there is no chance of it starting. It should fill up to the threads in about 15 seconds or so. Typically if its hi pressure related, it will continue to run after the ether is removed from the equation.

Probably also check fuel pressure for giggles and grins. The test port is on the secondary filter housing and has a 6mm allen head. I think the threads are 12X1.5, not positiv though. It should be the same as the icp sensor.