I filled up my 2005 6.0 leaving town last Friday evening, and about 10 miles down the road, I got on the accelerator once, and it probably took 10-15 seconds to go from 50 to 70. Over the course of the next 100 miles, it just had a serious lack of power. It sounded OK, didn't spit or spudder, the turbo was winding up....it just acted like it was powered by a little 4 cylinder.

I got into my brothers that night, did some digging on this site, and found the possibilities to be fuel filter(s), EGR, or Turbo. I called the local Ford dealer Saturday morning, but didn't have any Diesel Techs on hand that day. He did have someone that could change the fuel filters, so I had him go ahead with that. I picked up that evening, but it still acted the same way. I had to get back home, and figured it was good enough to get back there. Three hours down the road, I fueled up again, and within 20 miles, it seemed to be getting a little more zip back to it. Within the next 60 miles, it seemed to be back to normal.

I'm chalking it up to a 'bad' tank of fuel. I had to call the Ford dealership to ask another question, and asked the service guy about it, and he said it's possible, and that if they somehow got a little gas somehow mixed in, then 'loss of power' would be the result, without throwing the 'water in fuel' indicator.

What are your guys (and gals) opinions? Anyone recommend a conditioner or other treatment to help prevent any long term affects? I called the fueling station and they claimed they haven't had any other complaints.

 

The 6.0 is sensitive to fuel quality/cetane value. If you got a low cetane (same as octane) it could show a power loss. Most diesel fuels are a 40 cetane but these engines like 45 cetane to run best. I run premium diesel with 5% soy added. When I have to get fuel on the road I look for premium fuels which are sometimes available at truck stops. Might not be listed on the price board. Just have to drive in and look at pumps.

 

If this is the only time it's ever happened I'd pick up a bottle of additive that has a cetane booster in it and carry that with you just in case. Also don't forget you can stop after 100 miles and add more fuel to dilute any bad stuff. I try to only buy from stations that sell a good volume to make sure I don't get old diesel that has gone bad. That's not good for the injectors.

 

All has been well with the truck until yesterday. After pulling a horse trailer for about 60 miles last night, the exact same symptons popped back up. They continued for the next 60 miles with the trailer attached, at times only allowing max speeds of 50mph on the flats. After disconnecting the trailer, same thing for the next 50 miles, only it got so bad at one point that the truck wouldn't pull up a small hill on it's own. After shutting it off for a few minutes, it started right back up and limped in to a dealer.

They called today and said the #1 & #6 injectors are bad, and they should have it done tomorrow. I'm just wondering if they truly went bad on their own, or if something else caused them to go bad. And if they're bad, how close are the other 6 to going bad (I personally suspect a bad/weak fuel pump...but I dont' have anything to back it up). This problem concerns me a bit, because several of us are heading west with a full trailer on a hunting trip in 2 weeks, and if this thing fails me, I can't say I'm going to be a happy camper.

I've loved the truck up until now, I just don't want the snowball to start rolling with this. Has anyone just had the injectors go bad, and that's it.....end of problems once they're replaced? Also does anyone know if their scanners show fuel pressure, or can one only get that information by hooking up a gauge to the line?

Truck is completely stock with 40,000 miles.

 

how low into the tank were you when it started acting up? If the station had gas in the diesel it would stay floating on top of the diesel so when you get low you are starting to see that in your fuel. You could let it sit over night then siphon off the top layer (hose just long enough to reach fuel) and see if you got any in there!
Cetane is not the same thing as octane! Octane is a rating of how well the gas is resistant to igniting, Cetane is rating how fast it ignites. Higher cetane would reduce power because fuel is igniting too soon in the stroke trying to push the piston down before it is anywhere near the top of its stroke (max compression)

 

Are you sure about this? I had to pump out a tank at work that accidentally had gas added to the tank. Even after several days sitting in 5 gallon buckets there was no visible separation, but it did smell more like gasoline than diesel.

 

put five gallons of diesel in 1 bucket. five gallons of gas in another and five gallons of water in another. Then weigh each bucket! Or try it in a clear glass it will seperate out due to different specific gravity. you have to multiply specific gravity by 8.34 to get the weight of a gallon or divide it by the same!

 

Well I don't know about all that. I've seen water separate before. I didn't see any separation in the gas/diesel mix, but maybe the reason it smelled like gas was because it was all on top. With the cost of fuel nowadays I might have tried to salvage some of that diesel if I knew it separated.

 

Diesel fuel/ gas mix is a good bonfire starter though quick ignition long burning to get wet wood going!!!!

 

I had actually also posted this to the 6.0 folder, and posted this follow up there as well: (Summary....I'm no longer conviced that I had a bad tank of fuel....I think it was more coincidental than anything. To answer your question though, I first noticed the problem about 10 miles after filling up.)
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Got the Truck back last Friday, and I still thought it was lacking power. Had a friend drive it, and he thought it was fine, so I started second guessing myself. I hooked an empty flatbed to it, and was then convinced it was still bad.

Took it back to the dealer this morning. They confirmed that fuel pressure was too low, so they replaced the pump. The pressure was better afterward, but still not quite up to par. They called and asked if they could replace the filters (which were just replaced 2000 miles ago at a Ford dealer 4 hours away when I first started having the problems).....I said go for it. They called back and said that took care of it.

My Ford dealer is telling me that only one of the filters that they pulled out appears to have been changed last month, and that IT wasn't a Ford filter. Now I'm not one to argue much over the quailty of one brand filter over the other, but when I pay $100 for a pair of Ford filters installed, that's what I expect get. I called the other Ford dealer, explained the problem. He talked to his mechanics, and they say there is no way they would have used anything but a Ford filter....but is going to still reimburse me the $100. I'm guessing some young punk decided he wanted a new set for his truck, and decided to throw his Auto Zone brand into my truck thinking that no one would ever know the difference or catch it. Had I been more diligent in my filter changes, that probably would have been true.

I'm pretty sure the unchanged filter caused the pump and/or injectors to fail.

I'm picking my baby up in an hour, so hopefully, it'll have the nads that it used to have.

Lessons learned....change filters as prescribed, run cetane booster additive on a regular basis, and drive it like I stole it occasionally (I think I already did the last one, but I'll just have to be more diligent about it from now on.)

 

Below are a couple of links to some interesting sites with tons of information about diesel fuel quality

http://www.dodgeram.org/tech/dsl/FAQ/diesel_fuel.htm
http://tdiclub.com/articles/Diesel_Fuel_Guidlines/

 

It is possible that the filter caused this problem, but I doubt it. I think you got a contaminated batch of fuel, moreover, I believe it was water. This would most definitely be the case if the injector tips are damaged or missing. H2O molecules are physically larger then fuel molecules, so passing said water through a hole of insufficient size will damage it. This doesn't explain why your truck ran better for a few days, but it is easily diagnosed by visual examination. Gasoline contamination would cause injectors to stick and the engine to misfire, but it would take something like 30% or more and would be readily detected by smell. Given that the pump and two injectors went south about the same time, I suspect long term water contamination caused it, and I'd bet you still have water in your fuel tank.

 

The 6.0 Engine has known issues with head gaskets, head bolts and injector reliability. You can use a good additive like Stanadyne performance formula that boost cetane and cleans/lubricates the fuel side, but Ford is suing IH over these issues for a reason. I'd check and see if there are after market injectors out yet that fix this problem for the long term.