Air in lines or bad lift pump?
 

OK. I hope some of you are patient enough to read all of this. I changed my fuel filter a few weeks ago and the cap (factory fuel filter housing) was on super tight. I had to use a breaker bar to break it loose. The cap looked slightly cross threaded but I got it back on with new filter installed. I drove it a few miles and it died, after I noticed fuel all over the road. Towed it home, re-installed the cap. Had to crack the lines to get it started again but cranked right up after cracking one line. Went a few miles and after it heated up it died again. Cracked the fuel lines again, and again it cranked right up. Repeat process two more times, same result. I don't see any leaks now but Im still getting air in the lines somewhere. I have no check engine light or codes coming up.
So the question is could my lift pump be going bad, could the cap or filter housing be letting air leak in without fuel leaking out. I am on another forum and they kind of have me chasing my tail. :dang:

It could be a combination of both of them. What is your fuel pressure? I would suggest getting a new filter cap first. Napa carries them and it should be about $15. Here is some more reading for you VP44 Diagnostic

Yeah I actually read that a few days ago and thats when I started thinking lift pump, but I dont want to spend 600 bucks on a new one if its only air getting in the system. I will buy a new cap tom and see what happens with that, Im tired of towing my truck home though.

I vote cap because if the lift pump went; you would not be getting air in the lines. A guage would tell you for sure though. It'd been a few years, but don't they have O-rings on them? If so what does it look like?

I put on the brand new O ring with the filter when I changed it. I will put a new one on when I get the new cap in.

Ok. I finally got my filter cap and my gauges in the mail today. I will install them in the A.M. I need to know what I am looking for on the gauge. Do I need to drive the truck under load or can I just check it in neutral? I dont really want to have to tow the truck home again so I am a little sketchy about driving it around in case it dies again.

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O.K. I got my parts put on today and when I pulled the fuel filter I noticed that there was almost an inch of a jelly like substance on the bottom of my fuel filter. There was also a ton of sand and junk in the bottom, not to mention the banjo bolt was totally corroded. I got it all cleaned out and put the new banjo bolt on that came with my fuel pressure gauge. Got it started back up and Im holding 15psi at idle. I havent gotten a chance to drive it under load yet (need to have someone follow me in case it dies again and I need to tow it).
Anyway, I guess the jelly stuff was algae??? Still no check engine light, so I guess its just trial and error from here on, unless anyone else has any ideas.

15 @ idle is good. No clue about the jelly. Bottom of the tank maybe? You didn't take a pic did you? Did you clean it out before when you replaced it? I just realized your 30min from me so pm me your number if you want to come up for help sometime.

I did take some pictures after I started cleaning it but you can still see a good deal of junk down inside of it. Also took a picture of the corroded banjo bolt.
http://smg.photobucket.com/user/hutchfball26/media/20130728_121157.jpg.html

OK well I dont know why the pics wont show.
Anyway I took the truck out today and ran it for a while, got it up to highway speed. I went from running 15psi (at idle) right after I cleaned out the filter to 13psi now. I guess the filter is getting more crap from the tank in it again.
I was dropping down to 6-8psi at wot but the truck was pulling hard, after it warmed up. Is that good enough or should I be looking for a new lift pump?
After I shut it off I let it sit for a few hours and started it back up to go to the store, felt like it was pushing some more air through it because there were some fairly bad stutters but they went away pretty quickly.

you are going to kill that injection pump...

sounds like you have a bunch of crap in your tank...run that thing till its just about bone dry and drop your tank and clean it out...then hang it back up and fill it up with diesel.

change your fuel filter again and put a better lift pump on there, or stretch the spring a bit.

you want no less than 10PSI at ALL TIMES!!! (this includes WOT)

more ideally would be 14+ PSI at all times to keep fuel constantly returning to the tank which will help cool the VP44 down. (overflow valve in vp44 opens at 13psi.)