So, today I did a dumb one...my truck is a 92 F250 with a 7.3 IDI. A couple of years ago I drained the fuel out of another truck that was being parted out. I had stored it in a plastic 5 gallon pail with the cap screwed on tightly and it was stored inside in the corner of my shed. I had kind of forgotten about it until this morning. My truck was down under 1/4 tank and I was worried I wouldn't make it to town so I grabbed that pail of two year old fuel and poured it in. Within minutes the truck started idling rough and smoking and when I would increase throttle it would get much worse...spewing massive amounts of blue smoke and running very rough. I switched to the rear tank which was on empty and managed to make it 10 miles to the closest station where I put in eight gallons of fresh fuel into that tank, then drove it back home. Its been running on the rear tank ever since which was never contaminated. Now: it idles smooth and has normal power on the highway with no signs of misfiring or smoke, but if I'm parked in neutral and wind the engine up with no load it starts smoking at around 1500 RPM and by 1800-2000 RPM its smoking badly and running pretty rough. The fuel filter was just changed last year and there's less than 1,000 miles on it. The injector pump and injectors are original with 130,000 miles on them but the truck had been starting and running perfectly up to this point. Like I said...it seems to run fine and has normal power out on the road but sitting still and running it under no load it smokes, misfires and shakes. Any ideas?

 

Siphon out the bad fuel, refill it with good diesel. That'll dilute any remaining gunk in that tank. Pour in a lot of diesel service too, to help make that residual gunk less apparent.

Then bleed the fuel lines up to the filter until all the new diesel has worked into the fuel lines. That should help deal with any gunk that might have infiltrated your fuel lines.

Then purge the air from your fuel lines and injector lines. Then, pull your diesel filter and drain out the diesel in the filter. Refill it with ATF. Put the filter back on. Start up the engine and run it until you have ATF in your IP and injectors. The ATF will help clean the injectors. Once the ATF is sitting in the IP and injectors, turn off the engine. Let it sit overnight. Then in the morning, fire it up and drive it around the block. After that drive, you should see an improvement in your idling and smoke. If there is still smoke and whatnot, then you might be overdue for a new IP and injectors. I recommend R&D IDI Performance for injectors and an IP.

 

I have dual tanks. I poured the contaminated fuel into the front tank but after it started running poorly and smoking I switched to the rear one and its been running on that one ever since. I pumped as much fuel out of the front tank as I could and as soon as I can I'll fill it with fresh fuel. I go back to work tomorrow so I won't get much time this week but I'll try the ATF in the filter as soon as I can.

 

Do the ATF sooner than later. No sense in running it rough with a stuck injector for a week, when you can put a filter full of ATF in rather quickly.

 

One thing I forgot to mention: I have dual exhaust on this truck and it smokes out of both sides. Maybe a little more from the driver side but lots of smoke out both sides so I'm thinking this is more of a pump issue. I'll try to get to it after work some night this week. Its not my daily driver so I won't be running it again until I get time to work on it. I'll update with the results.

 

One thing you might consider is replacing the fuel filter when you fill it with ATF. It's pretty cheap and since you have to dump the bad fuel out you MAW...

 

I was going to mention this also when I read it last night.
Dumping out the old fuel then refilling the same old filter with ATF Diesel or what ever......
just raises the chances of getting contamination on the clean side of the filter where
it pulls fuel to the Injection Pump and Injectors. You can not have too clean of fuel going
into the system.

Several years ago on another Diesel Forum, a guy was dumping the fuel from his old filter
into his new filter. His thought, why waste the fuel? WOW!!! Talk about a dumb move.


Charlie

 

I should have added that if you are doing the ATF filter deal, you should use a new filter if you can get access to a spare filter. Only in a special situation (like stuck on the side of the road, on a roadtrip somewhere remote, etc) should you reuse the old filter.

 

I usually buy the Napa gold filters but those are around $50 each. I'll shop around and see if I can find something a little more reasonable.

 

Here are two fuel filter options that should save you money:

 

Mine has the open bottom and removable cover with the water sensor so I'm currently using this one in the Napa version:


I ordered the Motorcraft one on amazon last night, should have it on Thursday:

 

You might want to move away from those types of filters. They are notorious for leaking and air intrusion. Find a filter with a thread on the bottom for draining water.

 

Success! The new filter arrived yesterday so last night I filled it with as much ATF as it would hold and put it on. It started right up and stumbled and surged a few times. As soon as it smoothed back out I shut it off and let it sit overnight. This morning its back to normal...no more smoking and its running smoothly again. Thanks everyone!

 

Glad you got it running smoothly.

 

ATF is magic.