Hello again.

I was hauling hay on a fifth wheel trailer and my '06 F350 started jumping again. I have the six speed stick, and the 6.0 diesel. I was accelerating from 1900 after slowing down for potholes, and eased the pedal down. As the truck started to find boost again, the truck started surging, bucking, cutting out, I really don't know which. My Dad was riding shotgun, and he thought I must be having a seizure or something. This time the rpms fluctuated in a range of 250 from high to low alternately, as visually observable on the tach, but no codes were tripped.

I have fought this problem over and over again. I have always thought this truck was a bit anemic with regards to power. I have had the fuel filters changed twice since original, and I am at 29,000 miles. This seems to be the only thing the dealership has to offer on the subject. They are strongly suggesting, if not requiring me to do so again today as part of their investigation. They did replace a cam sensor and seal on the back of the motor a few months ago. It was leaking oil, and they thought it might be send false info to the computer. No leak now, and we are still bucking.

I have switched to synthetic rotella. I have been running pwer service for winter months. (last winter they were sure my fuel was gelling. I pulled samples and tried to get the fuel to gel in my deep freeze unsuccessfully). I have not run any soy forever. I have a new gravity flow highway fuel barrel, with a filter.

Note: my dad's '06 Dodge has been pulling from the same barrel. He has not changed his original fuel filter, and his truck has not missed a beat.

I am ready to pull out what little hair I have left. If anyone has a theory I could try to get followed up on I would grateful!

 

One additional note, this always happens on a uphill grade.

 

I had similar problems, but much later mileage, around 60,000 miles. It turned out to be a sticky turbo, the vanes were rusted up. If you idle a lot, it could be the issue. They also replaced the baro sensor, so in the end I can't say for sure what fixed it, but the truck flies now, no problems with hills, acceleration, nothing.

 

You should be changing your fuel filters every 10-15k miles. Your dads dodge uses a different fuel system, but he still shouldn't be running on original filters. There is one basic rule with diesels... keep the damn fuel filters clean.

Has the changing of the fuel filters solved the problem before? If so then you don't really have a problem. If it doesn't then you could have turbo issues, a leaking intercooler boot, bad injector, etc etc. I would find a dealership worth a damn.

 

Dealer did an egr function test, and changed fuel filters. They also put a recorder in the cab. Push the button, and you record 15 seconds prior, and 35 seconds after. Tech says it is monitoring 20 different areas. Capacity of recorder is 4 recordings.

Fuel filter change was $142. Raining today, so I can't get to a load until tomorrow. Empty, the truck feels the same for what it is worth.

Would be interested to find a shop with a dyno. My service manager is making efforts, but his regional man from Ford is tying his hands a bit.

Didn't mean that Dad was right, but going 30K without changing fuel filters makes me feel like contamination of my fuel supply can be eliminated from the list of possibles.

Thanks

 

Well let us know if the filters solved it. Never heard of the recorder deal thats pretty neat.

Dyno's are pretty easy to come by and very affordable just do a yellow page search. Not sure what all thats going to tell you though. Especially without having a baseline of how your truck started.

Sorry didn't mean to offend you about your father or anything that wasn't my intent. Yes it does mean clean fuel, but it also means a strong fuel supply since there is nothing to slow it down with clean filters.

 

07 f250 King Ranch srw 6.0 fx4 42,000 miles
I just got my truck back last week from the dealership with the same irratic idle and RPMs. Turned out my ICP sensor was to blame for the RPM irregulaties. https://www.ford-trucks.com/forums/8...with-6-0l.html is a link out of the tech folder I saw that I could have diagnosed the ICP sensor was bad. The diesel tech at the dealership told me the same procedure he used. By the way, I buy my fuel filters from an International supplier that deals w/ big rigg 18 wheeler stuff Fleet Pride of corpus christi, Texas. $38 dollars done myself.

 

Ford's #1 cause of injector failure is low fuel pressure (most commonly caused by plugged up fuel filters). 15k miles is TOPS! You would be better off at 10k miles. Injector problems are expensive AND guaranteed in a 6.0L Ford IF you continue to go 30k miles between filter changes.

Divedeep1 is correct - buy International filters and change them yourself and save a lot of $$'s.

 

These are similar symptom I had that turned out to be the harness chaffing on a valve cover bolt (drivers side valve cover)...you can check this very easy by grabbing the harness (with the engine at idle) and wiggling it around, working from front to back, and see if you can get it to cut out.

 

Thanks for all the input.

I have a list to go through. I will do some wire shaking, and the icp testing while it is still raining.

I have an international dealer in town, so I will check out the filter prices there. I know of a powerstroke 6.0 bought with a lemon reputation for power that he "fixed" with an international program. The owner and I went to college together, so I think the information is credible. He wasn't worried about losing warranty though.

Thanks again.