I have a 2001 excursion 7.3 with under 100k. Never had any problems since I bought it, I run it once about every 1-2 weeks. The other day I was taking apart the rear panels to see if I have room for custom bench seating face eachother along the whole length of the interior. I was looking at how the rear ac is behind the panel and then started the truck and just left it idling while continuing to work. After idling for about 5-10min the truck started knocking really loud, I looked up from the back and saw that the drivers seat was shaking back and forth as well as the whole truck shaking very hard and then the engine stalled. It almost felt like the truck ran out of fuel. Then when trying to start again would stall and knocking, wouldn't idle and had to floor the gas to keep it from dying yet barely any throttle response or revving. Tank gauge reads about 1/10. Truck had been sitting for about a week and a half to two weeks. I was afraid of possibility of someone tampering with the fuel (going to buy locking tank tomorrow). Then thought possibly water from condensation or fuel gauge was off, so poured in 2gal diesel and still problems. Left over night and now I can get it to idle but sounds very rough and knocking.... Sorry for such a long post. Any suggestions would be great. Was going to buy some tank additives to try. Either Power Service "Diesel Kleen" (grey), Power Service "Clear-Diesel" (white), Power Service "Diesel 911", or Gumout "Diesel Fuel Treatment". What should I do? Please help.

 

I would put a little more fuel in it(5 gals min), the pick up foot in the tank could have "broke" off. Also change your fuel filter. After changing filter and adding fuel cycle the key about 3-4 times(turn key on let it sit for a min then off...repeat) to make sure the fuel bowl is full before starting it.

 

Sounds like it could be a UVCH problem. Do you have any way to pull codes?

Gonna move this over to the 7.3L PSD forum.

Stewart

 

I am leaning towards a pre-engine fuel delivery problem. Put some fuel in the tank. 1/10 tank is very low (and bad for the injectors). Its common to suck air and cause damage. Especially if the pick up foot is damaged or missing as mentioned. If that's all good, try disconnecting the hose to the rest of the fuel pump and blowing low pressure air through the lines. There are screens in the tank that get clogged.

Once that is done check the fuel filter, make sure there is adequate flow (cycle key off and on to check fuel pump operation). Then check oil level.

Do you have any way of checking ICP, fuel pressure, etc?

Many people might jump at the CPS. I don't think its the culprit here, but they are cheap...

Stewart could be on to something but usually a bad UVCH doesn't cause a stall. Start with what I've suggested (and those before me) and we will see where we go from there. Hopefully its simple but maybe its more complicated like two bad UVCHs.

Also, once its fixed, don't forget to report back!

 

Yeah, not normally, but my Ex aint normal.

Years ago, when I had my gotta-shim-my-UVCH problem, a couple days before my Ex completely quit, the UVCH would rear its ugly head for a few seconds at a time. Just before it quit for good, the engine stalled a couple times.

It does sound like a fuel problem, but I didn't wanna discount other common problems the symptoms could also point to.

Stewart

 

Generally UVCH will have an SES light with it too.

Oil level was my first thought, then fuel, the 2 gallons you added could be enough, but you still have some air to work out.

 

I know you didnt say but do you have a CEL?

 

I agree with both - first fuel up and cycle the key a few times to clear the bubbles. If that doesn't solve it, Click here [LINK] and ohm out your injectors.

 

My '01 Excursion did this to me after sitting for a few weeks and not being driven. It started ok, then broke into a rough idle.

The problem was the fuel, it had probably turned or had water in it, so I went to the Auto Parts store, dumped a fully bottle of Diesel Kleen in and it was happy again and has been ever since.

My Dad drives it now so that problem doesn't happen anymore.

 

So It is able to idle now, still very rough and knocking, I added more fuel, and am going to put in the diesel Kleen like you recommended. I bought basically one of each of the additives to try. Is it bad to put them all in there? I would assume so. Which one is the best to use then? I have diesel kleen, clear diesel, and diesel 911...

 

Start with Diesel Kleen, gray bottle

 

Diesel 911 is only for clearing gelled fuel. Won't help you here. Edit: try disconnecting your ICP sensor and see if it idles better. This is free and easy......do you have a check engine light on?

 

Although it does sound more and more like a fuel delivery/quality issue, have you checked your oil level? It's just one more free and easy check.