I have posted in a couple of threads, most recently one I started in regards to difficulty I was having during a cross country trip from NH to Iowa, in regards to the 6.0L engine.

I am still learning and doing a bunch of reading, lurking around the site. There is plenty of info to gather! Anyway...

My MPG went down to about 11.4 while towing 1271 miles from here to there. I have been at my destination now for about a week. I have yet to see the MPG recover to its normal 15.5-16 MPG.

Is there a specific length of time before this average will return to normal? Or perhaps does this have more to do the period of time driven at the lower MPG?

I have become a bit sensitive to the operation of the engine, its efficiency and what it is doing. Knowing this will just add another piece to my understanding of how it works.

Thanks!

Eric

 

are you figuring the mpgs yourself, or are you using the thing on the dash

 

I figured them by hand. Found the digital readout to be about 0.7 MPG off from what I calculated. Still it is a general indication and something I can quickly refer to.

Eric

 

fuel quality is a big player in mpg. were at the stage to begin swiching to winter bleed as well.
a few things to check....
ficm voltage, egr valve, turbo operation, coolant level, oil quality, fuel quality, fuel pressure. you can also perform a power balance and relitive compression test if you have the ability

 

Just had the EGR valve replaced. It failed. The EGR may have been on its way out but there was no indication of a problem until I filled up at a rest stop in Rochester New York area. 20 miles later I pulled off into a campground for the night and then, in the morning went to hitch up and leave and the truck stalled, then once running and warmed up a bit, began belching smoke at low RPM, on the verge of stalling until 30 MPH or so was reached and then would run normally.

Long story short: 1. Bad tank of fuel. 2. Bad fuel may have accentuated a near failure issue with the EGR. 3. The EGR valve not working caused I believe black soot, residue to build up in the EBP Tube. 4. There was damage in the form of a score on the CAC tube which required that tube to be replaced. 5. I can't say for sure what caused the EGR Valve to go. Cold Carbon Stacking? it had 63K on it from what I can tell.

I have had the truck for about 2 months. Engine hours to Mileage indicates a 34.7 MPH average for driving.

I am finishing up a second tank of fresh fuel, it is running with additives to remove water, and I will be having an oil change, tire rotation and Primary and secondary fuel filters changed again on this coming Tuesday. Hopefully almost all of the treated fuel will be gone.

That whole episode was not fun. It would be nice to have a chart of places that have had "issues" with thier fuel. This may help some of newerfolks avoid junk! I like only the best for my new toy!

Eric