2003 f350 diesel 6.0 sporatic engine trouble

[boisdarc1]

i am not sure if this is related, but i added the correct amount of diesel kleen to my tank. later that day my truck-while driving slowly began to loose power and sound like it was under water. i pressed the accel and it just sounded like it either wasn't getting enough fuel, or was running on only a few cylinders.
when i got home i killed the engine. then restarted it and it fired up nicely.

well that's been two weeks and about 2 tanks of diesel. now if i kill it, i'm not sure when it will start. it might start up great, it might not. when i doesn't start, i can usually wait 20-30 minutes and it will start and run very roughly.

i changed the oil and fuel filters, added more kleen to no avail.

currently it is sitting in some parking lot not wanting to start. i'll try later.

not sure if i loosened some crud when i added the kleen the first time and now it's getting clogged in the ejectors???

anyone's opinion would be greatly appreciated.