Over a year ago my mileage dropped from 19 mpg to 15 mpg. I found that 5 out of 6 injector were bad so I replaced them with Don M 100 HP injectors. Since my truck has over 230,000 it this was my excuse to do some up grades. New CP3 33%, rebuilt tranny, new turbo, larger tires 285's. I was running just a quad race box but after all the mod's I bought a smarty and ran it on sw7 until UDc came out.
I have tried multiple cp3 pumps, multiple pusher pump's, ran stock program, checked brake calipers (found one sticking), jacked up the entire truck to see if we could feel and kind of drag somewhere, replaced crack sensor, replaced air filter, replaced all fuel filters, increased tire air pressure, tried several fuel stations and I am probably forgetting so other stuff we tried. None of this had made a difference. I used to be able to get 580-600 miles on a fill up now the best I have done is 495.. Any other idea's on what to check? I know once winter fuel goes away I will gain a little but looking for some others things to check. In have been wondering about MAP, air intake sensor, intercooled etc.. Also calibrated my speedo, using ggps, road markers and I'm have it so the truck is going about.5 mph faster then speedo. One thing I have noticed I'd I tend to cruse at 18-25% engine load which makes me wonder if I have some drivetrain drag somewhere. Thanks guys
I have tried multiple cp3 pumps, multiple pusher pump's, ran stock program, checked brake calipers (found one sticking), jacked up the entire truck to see if we could feel and kind of drag somewhere, replaced crack sensor, replaced air filter, replaced all fuel filters, increased tire air pressure, tried several fuel stations and I am probably forgetting so other stuff we tried. None of this had made a difference. I used to be able to get 580-600 miles on a fill up now the best I have done is 495.. Any other idea's on what to check? I know once winter fuel goes away I will gain a little but looking for some others things to check. In have been wondering about MAP, air intake sensor, intercooled etc.. Also calibrated my speedo, using ggps, road markers and I'm have it so the truck is going about.5 mph faster then speedo. One thing I have noticed I'd I tend to cruse at 18-25% engine load which makes me wonder if I have some drivetrain drag somewhere. Thanks guys
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