Background:
Its a 1997 Silverado k1500 5.0 4x4
Its had a new engine block (2 yrs old).

A couples months ago I noticed that when ever I reached a cruising speed on the highway, my truck would start to lose power and sputter. (Check engine light would turn) I would then step on the gas and the sputtering would stop. (and the check engine would turn off) It would only lose power and sputter whenever i would let go of the gas gently. I never thought much of it, until, my truck left me stranded on the side of the highway at 2AM. The truck still had all power and accessories working, its just the engine would not start, it sounds like it cranking, it just wont turn over. It has fresh gas. (no check engine light ever turned on). I've been told it might be a blown head gasket, fuel pump isnt working or I have a clog in the fuel line somewhere. Any suggestions? I plan on doing the work myself. Just need a helping hand in what I should be looking at...

... also, the engine would make a knocking noise before it died on me, it would make that noise whenever the engine was cold. The noise would pick up as the RPM's picked up. But after the engine warmed up the noise would stop.

 

1. find a buddy with OBD2 scanner and read codes.
2. knocking noise before it died? 1st sign of very low oil pressure. hopefully, it was just due to rapid rpms reduction. clicking on cold is typical of GM pushrod engines, don't worry.
3. so, now, that you have your codes read - you can either post them here for help, or look it all up in various sites, like this one here:
http://www.obd-codes.com/trouble_codes/
http://myweb.accessus.net/~090/dtcobd2.html

otherwise, you are looking at much guesswork and, most likely, very unproductive guesspairs - repairs on a guess.

CEL is, basically, for emissions only. does not really tell you anything about engine troubles. should have replaced that fuel tank cap WAAAAAAAY back, bud.

of course, you could do all procedures listed here:
http://autorepair.about.com/cs/faqs/l/aa042603a_1.htm

but i reckon, you'd better off having truck towed somewhere easy to work on.

 

this doesn't sound good, better start at the basics with checking all the fluids and report back

 

If you don't hear the fuel pump prime at each start up the fuel pump is for sure suspect, as for the knocking since its a remanufactured / not original I would be suspect of the oil pump but it could also be that that valves need to be adjusted knocking can also be a timing issue or weak spark.
I'd have the battery checked
throw on a new fuel filter
pour in a few bottles of Techron