Diesel MPG drop
#1
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Over the past few tanks of fuel, my mileage has been down by as much as 5 mpg. Around town I've averaged about 21.5 mpg and highway, though reading 29/30 on the display is only calculating out to about 26 mpg.
I've changed the oil, oil filter, air filter and fuel filters.
I'm not sure what else to check that might be causing more fuel usage. What am I missing? What else should I be checking?
I've changed the oil, oil filter, air filter and fuel filters.
I'm not sure what else to check that might be causing more fuel usage. What am I missing? What else should I be checking?
#4
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My actual mpg is 27.5 to 28.5 but display show 32 or more i do 95 percent hwy.
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RS-America (10-26-2020)
#7
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New tires, proper pressure. Mieage dropped well after the tires were installed. Vehicle tracks straight, so alignment is good, I'm pretty sure.
Winter blend fuel doesn't hit here until October at the earliest and, historically, has cost about 1 mpg, 2 max.
Oh, and no body in the boot.
Winter blend fuel doesn't hit here until October at the earliest and, historically, has cost about 1 mpg, 2 max.
Oh, and no body in the boot.
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#8
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Originally Posted by skiahh
New tires, proper pressure. Mieage dropped well after the tires were installed. Vehicle tracks straight, so alignment is good, I'm pretty sure.
Winter blend fuel doesn't hit here until October at the earliest and, historically, has cost about 1 mpg, 2 max.
Oh, and no body in the boot.
Winter blend fuel doesn't hit here until October at the earliest and, historically, has cost about 1 mpg, 2 max.
Oh, and no body in the boot.
Mpg drops significantly compared to top tier....
#10
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Good call. Forgot about the gallon of that in the garage!
#12
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My mileage has been down since the software update too. I'm not sure exactly how much but, probably in the neighborhood of around 2-3 MPG on average. When I thought the update fixed the lag that seemed a totally acceptable trade off but, given that the lag returned once it got hot I'm not quite as happy about the loss in MPG now. A tune and delete is looking better and better.
#13
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Mine was fine after the software update. Definitely not the update here.
Maybe it was a bad batch and adding the diesel service will clean out any remaining crap.
Or maybe I need to take the air intake apart again and see if it's goobered up.
Maybe it was a bad batch and adding the diesel service will clean out any remaining crap.
Or maybe I need to take the air intake apart again and see if it's goobered up.
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Eskimo1 (09-29-2020)
#15
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