Ok so have been noticing my truck has been getting pretty bad fuel mileage. like 9.8-10.5 mpg the last 5-6 tank fulls. I know winter fuel SUCKS!!! and have been told that a 2-3 mpg drop is normal, but my summer mileage was up in the 15-16mpgs.
So I figured it was maybe the fuel I was using, so I changed stations, i havent filled up since, but half tank in, i got a hold of the ScanGauge2. ive hooked it up and one of the settings is is GPH. at idle in gear its up 0.80-1.02, where when its in neutral is down around 0.50-0.60. Now i dont know if thats good or bad, thats question 1.
my other question is what can be causing such bad fuel mileage. I have good oil in there fresh motorcraft oil/fuel filters. The truck is a 2004 f250 with 70k on the clock and with a 4 mbrp tbe and sct tuner with SRL tune on it. also the truck has 33x11.5r17s (fuel mileage dropped maybe 0.5mpg after the rims/tires when on). I really havent driven the truck hard, other then the once in a blue moon full throttle run to clear out and stretch the trucks legs.
I hooked up my AE, looked at all the sensor readings, nothing really stands out but my FICM is reading at 47.5volts at idle and then while driving is drops down to maybe 46v. I have no driveablity issues, truck start like a champ every morning. Being a ASM at a Ford dealership and having years as a technician, ive seen all the signs and issues with 6.0s.
The problem is this truck/platform is all new to me, ive owned the truck for 7 months, so im learning more and more everyday. being at the dealership helps but, im just looking for other insight.
If more information is needed or anything along those lines please let me know. and trust me ive been using the search button a lot (work has been nice a slow with all the "worst storms of the seasons" that has hit my area
Thank you in advanced