I have a 2000 f250 7.3 with 137,000mi on it. CPS has been replaced. It has an f5 DP tuner, AFE cold air intake, 4" flowmaster with 4" tailpipe, and close to stock tires. About two weeks ago while running 75mph I noticed a slight sputter, when I gave it some throttle it began to sputter violently, then shut off and started for a brief moment after taking fuel filter out and inspecting( >1/4 tank and 272 on trip). Towed to local garage, which put 4gal fuel in and said truck ran fine, fuel gauge was just bad and I was dry.(I did not replace it). I put 15gal in when I picked it up, giving a grand total of 19gal. I know I've put over 20gal in before.

Today, same thing while running 50 mph, violent sputtering. Shut off at traffic light, put chip on stock, started back up and limped truck off road, still sputtering.(< 1/4 tank and 215 on trip)

I had the chip updated, and when I put it back on the injectors were noticibly louder ( sounds like UPS running down the road, the exhaust sound is drowned out by rattle). When I asked DP about it, they said more injector noise is common.

Any thoughts would be appreciated.

 

Mine did the same thing and it was a loose connection on the switch for the tuner. When it does it look at the face of the DP and see if it is a number or scrambled. Mine was cycling through all the little dashes.

 

Any SES lights on the dash when it starts acting up? Just from your brief description, sounds like you may have a fuel delivery issue when it gets low. Clogged pickup foot in the tank.

 

I did not notice any changing on the switch, and when it does act up it is done and the truck is loade back on the wrecker.

No SES light, but I am thinking it is in the fuel pick up. But what is confusing is that the fuel volume has been different at the two occasions.

Thanks

 

Running it low (>1/4 tank) the first time may have allowed some crud in the bottom of the tank to get stirred up and get into the pickup foot. The fact that you have no SES light makes me think its a fuel delivery issue - either pump and/or pickup tube.

 

Try to not let it get below 1/4 tank and I bet you will have no more issues. I am thinking that there is a crack in the pick up tube when it is below 1/4 tank you start sucking air.

 

Or the duckbill valve has a leak.

As a test, as Jim mentioned, never let your tank get below a quarter full, and see what happens.

If that stops this sputtering, we will then know that some worthwhile mods inside the tank will fix it.

Pop

 

All sounds logical to me. Thanks for the input guys, I'll give it a try.

 

Ah ha! The experts have spoken!

 

Another possibility is what happened to me, and that is the injector wiring harness that has a coupler under each valve cover. Mine sputtered so bad I had to coast to a stopping point on the highway and then it shut down. A big problem for early 7.3 PSD likes yours and mine. If it turns out that this is the issue replace with an OEM harness not one of the cheap after market ones available. Good luck and let us know what you find out.

 

Here is a picture of what caused my excursion to run out of fuel early. I did the Hutch/Harpoon to fix.

 

Here's a shot from Hutchinagusta that shows its shape and the reason why it has the name "duckbill".



Pop

 

What is the Hutch/Harpoon fix, and where can I find more info on it?

 

As usual, Guzzle has this covered!

See:
Welcome to guzzle's In-tank Hutch Mod Web Page

Pop

 

Yeah, I guess I didn't say but the little dohickey fell out and I was running out of fuel with maybe 4 gallons still in the tank.