7.3 Won't Start

[Isakson]

I went out this mornin to start my truck, and i waited for the wait light to go off, and i cranked and cranked, 4 times, each time turning the key off and letting the plugs warm up again. I'm in missouri, and i don't think it was very cold outside lastnite and at the end of the 4th time it sputtered and coughed and made some white smoke but thats it. i kept tryin a few more times and it just kept crankin really fast like normal but didn't start. the only thing i haven't done was treat this tank of fuel with Powerservice. i usually do. and it has new gplugs and gp relay and new wiring harness. should i look to see if they are unplugged? how do i do that. I had them put in.

**when they were put in the truck misfired because the wiring harness was broke, so the mechanic put anew one off a fedex truck that had only been on for 3 days, after that my truck runs fine.

could my lift pump be failing?

[Hank]

[Soot_Life]

sound almost lke you lost your prime in the fuel system.. is there a possibility the filter cap isnt tight or you have a loose line... if it puffed white smoke it got some fuel otherwise it would just be air... i know this isnt much help but it sounds similar to when i realized my fuel level sending unit went out

[Isakson]

well i had my fuel filter cap come loose when i was drivin, so i tightened it back, so idk wh'at it is, i dont smell any diesel at all, so i wouldnt think it would be loose. I did have a code for low voltage to IDM but i cleared it and havent rescanned it.

[Isakson]

Could this be from not treating my fuel? the Powerservice offers anti gel, injector lubricants, and Cetane boost "for easier starts" idk what it is. should i drain the fuel filter resivoir?

[musclehead11]

This has happened to me a few times with my 7.3L. Each time was because I let my fuel level get down to low and water from the fuel tank got into the fuel/water separator bowl and just sat there. I had to take all the fuel out of the separator and put fresh diesel into it. After I did that I also change the fuel filter. When it was all done my truck started right up (with the white smoke), but after it ran for a few minutes the truck ran perfect. I suggest trying this out before doing any major repairs.

[Isakson]

so should i go drain the fuel bowl, then try to start it? or will it not prime by itself? it just cranks forever

[unholy1]

This may sound dumb, but have you checked the oil level? I just got a rebuild on my 7.3 and it's been using a little oil. It has slowed down now that the rings are getting seated. Anyhoo, one morning she wouldn't start. Similar to the symptoms you outlined. (You could tell that the injectors weren't firing.) It was about one-quart low. I added a quart and it fired right up.

[musclehead11]

Yeah drain the fuel bowl, you can open the yellow relief level on the back and also suck all the diesel out with a siphon. Make sure the bowl is clean from grim inside it then refill with clean diesel. Don't let the truck prime it because the fuel in the lines still has the water in it from the tank. After the truck starts it will be able to burn off the water in the lines. Id also get some diesel fuel additive and put twice as much as they indicate on the bottle in the tank.

[Isakson]

k, i usually just pour it in, i dont measure the amt out of additve i put in, will that hurt it? and i overfilled the oil a while back but now i think it is normal level...and i live on a slant so i dont think the oil reading will be accurate... could just pouring powerservice w/out measuring it hurt my truck? cuz i understood it wouldn't cuz it could run on pure powerservice