truck is down, please help

[silverado3500]

The truck is a 2000 f-350 7.3 6 speed. I installed the return regulator mod about 900 miles ago, along with the pre pump and in tank mods. Went to the store tonight, and when I came out, truck started, but felt like it was missing. I checked my fuel pressure gaguge (which I believe is fairly accurate) and am only getting 20 psi. The truck runs, but is not very drivable, and I especially need it this week for work as the power is still out (no thanks to katrina).
I do have a pre pump filter, however there was about a 200 mile gap between when I did the pre pump mods and when I installed the filter. When its light in the morning I will be able to do a more thorough check for leaks, however I could find none tonight, nor was there fuel underneath the truck. Any suggestions are greatly appreciated. Oh, and I forgot, now service engine light either.

Thanks in advance, and I apologize in advance for any delayed responses to questions, however my internet access is greatly limited due to having no power.

 

[95_stroker]

If your truck is missing you might have a burnt injector harness. Take the oil filler cap off the valve cover and see if it smells like burnt electrical. Or you can unplug the valve cover harness one at a time and see which one makes the least amount of difference in the miss and that is probably your dead hole. One other way is to take a infra-red heat gun (if you have access to one) and shoot the exhaust manifolds right at the cylender outlet and find the cold one(s).

Mike

 

[silverado3500]

I'm about to give those tests a shot, thanks

 

[95_stroker]

Let us know what you find.... not sure if the fuel pressure being low is related to the miss? Seems unlikely but theres only one way to know for sure I guess.

 

[Tbar]

Go with the obvious first by looking at the fuel delivery system. A burnt injetor harness won't cause low fuel pressure.

1) Change your prepump filter. If you did the in tank mods and removed the screen then your filter is going to pick up the course heavy crap in the bottom of the tank. You would be real supprised at the crap that can be found in the bottom of a diesel tank.

2) A common error in doing the in tank mod is not getting the rubber boot back in the right place. If it is too low it will colapse against the bottom of the tank and cause a restriction. This will be most noticeable when your tank is closer to empty.

3) Another common mistake is when you put the tank back in the truck is getting the rubber pick up hose crimped causing a restriction.

4) It is possible that you have a leak in your prepump mod that is sucking air. It will not necessarily leak.

5) It is possible that your fuel pump is on the fritz but I would check everything else first.

A vacuum gauge might be helpful in finding the problem.

If you don't have that then try a piece of clear plastic hose. A restriction in the line is going to create a vacuum which is going to cause suspended air bubbles to release. Find a piece of clear plastic hose and put it in line in different places. At the tank, before the prepump filter and before the fuel pump.

If it is a fuel restriction problem or a leak and you find air bubbles you will know where to start looking.

Good luck.


Tbar

 

[bdp]

first check if pump is running. If it isnt check fuses and inertia switch.

 

[POWERSTROKEN]

I just had a similar problem with my 2000 E350 PSD van. After almost $2000 spent and 2 different shops visited it seems my problem is in my fuel tank. The last thing done is the fuel line was inhooked at the frame mounted pump and air was blown through the tank. This solved my problem and I have done it 2 more times until I can drop the tank and see what the problem is? Something is clogging the screen/sock in the tank?