Very Poor MPG
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Very Poor MPG
last 2 tanks of gas i filled with i got less than 8 mpg in my 01 7700 5.4 i changed the plugs,fuel filter,oil to 5w 20,air cleaner, also cleaned the maf put in a tank of v-power and fuel injector cleaner didnt make the slighest difference any advice will be appreciated thanks.......
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From: Louisville,Ky.
Welcome to the forum
Sounds like a fuel curve problem. Is the truck warming up to the proper temp? If not, it will run rich because the computer thinks that it is cold.
It may be worth the cost of an hr's labor at the Ford dealer to have them drive it with their scanner hooked up. It reads realtime data and will show any problems in the fuel/timing curve.
Sounds like a fuel curve problem. Is the truck warming up to the proper temp? If not, it will run rich because the computer thinks that it is cold.
It may be worth the cost of an hr's labor at the Ford dealer to have them drive it with their scanner hooked up. It reads realtime data and will show any problems in the fuel/timing curve.
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truck is warming up fine have a warranty so i brought it in they said nothing wrong with it go figure the moron said its the way i drive and i drive like a old woman beacause of the fuel mileage issue even romping on it shouldnt be that bad
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From: Louisville,Ky.
HMMM, Did they tell you the instant mileage that the scanner gave? Mine came up 14mpg @ 40mph. That's about what I get, between 13 & 14mpg. What gears are in the rear end? Is it the 4R70W or 4R100 tranny?
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From: South Kitsap County, WA
What are you using to compute mileage? The gears will be the 3.73's (26 or B6 code under "axle" on the door sticker), as they didn't offer 4.10s until '02. The transmission really doesn't kill the mileage at any rate. The truck doesn't require sduper, just a waste unless you have a chip.
Larger tires will cause the mileage to drop, but not by that many mpg's unless you're sitting on 44s and didn't reprogram the computer.
Sounds to me like you have a drastic parasitic loss. Something like a problem in the tranny, transfer case, or gears.
You have a 7700, so the mileage will be less than a standard F150 solely because the truck is heavier. I'm getting 13 now (50/50 driving on winter fuel mix), but can average 17 during the summer on long highway trips and 10 with a full load.
-Kerry
Larger tires will cause the mileage to drop, but not by that many mpg's unless you're sitting on 44s and didn't reprogram the computer.
Sounds to me like you have a drastic parasitic loss. Something like a problem in the tranny, transfer case, or gears.
You have a 7700, so the mileage will be less than a standard F150 solely because the truck is heavier. I'm getting 13 now (50/50 driving on winter fuel mix), but can average 17 during the summer on long highway trips and 10 with a full load.
-Kerry
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From: South Kitsap County, WA
Generally you'll have a sensor read the bad EGR, like the O2 sensors see more bad gasses getting out due to the increase in fuel consumption. If they hooked it up to the analyzer a bad EGR should have been detected, unless they only looked for engine codes and didn't actually look at engine sensor info.
-Kerry
-Kerry
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