My truck has been driving fine up until the very second the issue happened. No hard start, no smells, no nothing. Its been in the teens-low 20's here for the last two weeks but I keep my truck plugged in when I can. Im running a beans diesel sump, Airdog lift pump, stock VP44, stock injectors, stock turbo. Truck is an automatic 4x4 with 183,000 miles. Transmission replaced 3,000 miles ago. 

 

The issue: I was coming down a stretch of highway at 55mph, and had been for 20 miles, and the truck suddenly starting choking down and missing. I pulled over in a parking lot and could barely move the truck without it nearly dying. I went 50 feet, put it in park to listen to it idle, and the RPM's varied from 900-700 and suddenly dropping very low (500 maybe?). I put it in drive and the truck died before it even moved. Would rollover very strong but gave no hint to try and start. Got a tow truck to haul it to my house and hopped in my spare car. Got back home that night, let the air dog run for 30 seconds, turned the truck over for probably 10 seconds and it started. Idled completely normal with no strange RPM's. Drove the truck around the block a few times, getting up to 55mph in some places, and the truck behaved completely normal. Once I got home and the truck had gotten warm, the RPM's went back to going crazy. Not to the extent as early that day, but not normal. I have not driven the truck as far as 5 miles since due to fear of it shutting off once getting warm. This happened 3 days ago.

 

What would cause this to happen only when the truck is warm? Im getting a good steady 15 psi of fuel pressure. I have a new fuel filter on the way just to rule that out. I have also added some Diesel Supplement Wintergizer thinking maybe the filter got some gunk in it? Any suggestions would be great. I would typically let my normal diesel mechanic help me out but he seems to be covered up.

Might have had water that froze up or fuel gelling issue. With your sump on your fuel tank it's super cooling the fuel. Then the exposed fuel line to the blowing cold can freeze water or gell fuel rapidly. Like with my setup my fuel lines are on the top of the fuel tank then run inside the frame as much as possible. My AirDog 150 is behind the transfer case and out of the cold wind. I've been down to -35*F without an issue at all. I NEVER use any anti-gel products or cetane boosters at all. 

 

 

I've seen a local gent with a FASS in the standard outside the frame mounting it gels up every winter now. The filters hang down in the damage path of the front tires so all the snow and ice is slung on the filters causing the gel issue. Behaves the same way rung good till the fuel hits that gel point and down she goes. 

 

Way too much fuel line exposed to the cold wind...

Edited January 20, 20187 yr by Mopar1973Man

That does make me feel a lot better. I've let the anti gel sit over night and idled. It went a little rough on the way to work but smooth as butter on the way home and a little driving after. Do you not use anti gel because it is bad, or do you just not need it? I have not read much about it. I believe this was my issue. Thanks a lot for the quick response. 

2 minutes ago, nwilliams said:

Do you not use anti gel because it is bad, or do you just not need it?

 

No need for it. I have studied my local fuel and know the pour point of my local fuel. I'm the only owner of my truck and 330k miles and never had even one time to gel up my fuel. I was very picky and fussy about fuel line placement and keeping the cold air off the fuel system to keep the fuel heat up. I've still got my stock fuel heater / fuel filter then I know the fuel returned from the engine will always be a bit warmer. Like I said I've been down to -35*F without a single issue no cetane booster and no anti-gel used ever...

 

I've done the study work on 2 cycle oil in diesel fuel I can tell you that snowmobile 2 cycle oil has a much lower pour point (-50*F) than normal #2 winterized diesel (-20*F). I've been using strictly only 2 cycle oil for nearly 10 years and my last VP44 made it to 243k miles ALMOST a quarter of a million miles. Not bad in my book. 

 

Cetane booster tend to rob you of the BTU value of the fuel so the higher the cetane goes the lower the energy content. Another reason I use 2 cycle oil because it's a natural BTU increaser and cetane reducer. 

 

That leads me into my findings with the Quadzilla tuning. The only thing that the ECM can measure is cetane value. Being cetane naturally advances timing I started retarding timing in my tune and now in the 21 MPG bracket in the dead of winter with temperatures around 0 to 30*F. So understanding fuel chemistry helps a bunch. 

That's very impressive. Thanks very much for all of the information. I was worried my VP44 was kicking the bucket, but in Alabama this is the first time that I've seen 7 degrees in my life, and for sure with my Cummins. 

Thing is in Alabama they may not use any winter additives at all if they weren't prepared for cold weather, where is in Idaho at good name staitions it gets a good treatment. So in your case you may need to add some antigell if the store did not. 

Doesn't mean you need to add it every single tank. 

 

Also remember PowerService is  400:1 ratio so for 35 gallons of fuel your adding 11.2 ounces. Now, remember as cetane rises BTU's fall so the unneeded use of or overtreating the fuel will degrade MPG number greatly. Gasoline is just below the 120k BTU mark. 

 

The ASTM Labs States...

 

The ASTM Standard Specification for Diesel Fuel Oils (D-975) states, "The cetane number requirements depend on engine design, size, nature of speed and load variations, and on starting and atmospheric conditions. Increase in cetane number over values actually required does not materially improve engine performance. Accordingly, the cetane number specified should be as low as possible to insure maximum fuel availability."

 

 

Quite the balancing act you have to do right? 

The beauty of it is Alabama will warm back up just like here in NC. I work over a pretty wide area of the country and have never had the fuel gel either. I am usually buying fuel in the areas I work so I am sure I am getting some winterized fuel. The only thing I have ever added to my fuel is 2 stroke oil and did not start that until the truck had just over 200k on it.