Poor MPG
Tuned
Joined: Apr 2000
Posts: 393
Likes: 3
From: Merrill
Poor MPG
My brother has a 1996 F-150 4X4 with a 5.0 and a 5 speed tranny and 130,000 miles. he has noticed that the MPG's have really droped latley down to around 12-13 on the highway, and they used to be up closer to 18. the truck runs great and has no lights. he has tried changing plugs, wires, cap, and rotor, but it has not helped. I remeber seeing something on here about O2 sensors or some other sensors causing this does anyone have any ideas?
Thanks
Scott
Thanks
Scott
Junior User
Joined: Apr 2002
Posts: 75
Likes: 0
From: Port Gibson NY
Poor MPG
i think most vehicles require the O2 sensor to be replaced around 60,000 miles. not saying that is the problem. check the air filter(restricted air flow could cause poor fuel mileage). pcv? lower than normal tire pressure's, not trying to get off the sensor subject just trying to eliminate all other variables. tire size match the size on the sticker in the door jam? or are they the same size he had when he was getting 18mpg?
Post Fiend
Joined: Nov 2001
Posts: 14,947
Likes: 6
From: Topsfield, MA
Poor MPG
You'll want to check out the oxygen sensor, as well as the cats. Take it to a muffler shop, and see if they will test it for free, most places will. At 130k mi, if its stock, those cats are probably pretty plugged up. Think of small things that could possibly lower you're power, it doesn't have to be a screwed up air-fuel ratio. If you are low on power, you have to use more of the gas petal...using more fuel.
Primary rig is NOW TOTALLED :-X23 :
95' F-150 EB 300/6 5 spd with 4" Superlift, MSD, Ram Air, Gibson Exhaust, 32" BFG Muds
Some pictures in my gallery.
Then theres:
88' F-250 Superduty 351 + c6
95' Mercury Cougar 4.6L V-8
80' E-350 300/6 and a
3 spd column shifter. Top speed, 65mph, Go Baby Go!
The newest addition to the Ford family is a 99' Mustang GT 4.6L
Primary rig is NOW TOTALLED :-X23 :
95' F-150 EB 300/6 5 spd with 4" Superlift, MSD, Ram Air, Gibson Exhaust, 32" BFG Muds
Some pictures in my gallery.
Then theres:
88' F-250 Superduty 351 + c6
95' Mercury Cougar 4.6L V-8
80' E-350 300/6 and a
3 spd column shifter. Top speed, 65mph, Go Baby Go!
The newest addition to the Ford family is a 99' Mustang GT 4.6L
Tuned
Joined: Apr 2000
Posts: 393
Likes: 3
From: Merrill
Poor MPG
Air filter is good, tires have not been changed since the change. and it doesn't really seem low on power. I will have him get the cat's checked. what about checking the o2 sensors is there a way to test them???
Thanks
scott
Thanks
scott
Post Fiend
Joined: Nov 2001
Posts: 14,947
Likes: 6
From: Topsfield, MA
Poor MPG
Yeah, i belive u can take a volt meter and test the voltage. I dont have a book that tells me what it is sopose to be, so i'll leave that up to someone else, sorry.
Primary rig is NOW TOTALLED :-X23 :
95' F-150 EB 300/6 5 spd with 4" Superlift, MSD, Ram Air, Gibson Exhaust, 32" BFG Muds
Some pictures in my gallery.
Then theres:
88' F-250 Superduty 351 + c6
95' Mercury Cougar 4.6L V-8
80' E-350 300/6 and a
3 spd column shifter. Top speed, 65mph, Go Baby Go!
The newest addition to the Ford family is a 99' Mustang GT 4.6L
Primary rig is NOW TOTALLED :-X23 :
95' F-150 EB 300/6 5 spd with 4" Superlift, MSD, Ram Air, Gibson Exhaust, 32" BFG Muds
Some pictures in my gallery.
Then theres:
88' F-250 Superduty 351 + c6
95' Mercury Cougar 4.6L V-8
80' E-350 300/6 and a
3 spd column shifter. Top speed, 65mph, Go Baby Go!
The newest addition to the Ford family is a 99' Mustang GT 4.6L
Tuned
Joined: Jan 2002
Posts: 253
Likes: 0
From: BC Canada
Poor MPG
>My brother has a 1996 F-150 4X4 with a 5.0 and a 5 speed
>tranny and 130,000 miles. he has noticed that the MPG's have
>really droped latley down to around 12-13 on the highway,
>and they used to be up closer to 18. the truck runs great
>and has no lights. he has tried changing plugs, wires, cap,
>and rotor, but it has not helped. I remeber seeing
>something on here about O2 sensors or some other sensors
>causing this does anyone have any ideas?
>Thanks
>Scott
it doesn't sound like you have checked for error codes. it is easy to do with a piece of wire and cheap circuit tester. go to that dalidesign web site; they have easy to follow instructions. once you get the codes you will know where to start looking. i thought it might be hard to read your own codes without a scanner but it isn't. if i figured it out you can too! if one of your sensors is pooched it will give you the error code.
let us know how it goes.
Rusty,
>tranny and 130,000 miles. he has noticed that the MPG's have
>really droped latley down to around 12-13 on the highway,
>and they used to be up closer to 18. the truck runs great
>and has no lights. he has tried changing plugs, wires, cap,
>and rotor, but it has not helped. I remeber seeing
>something on here about O2 sensors or some other sensors
>causing this does anyone have any ideas?
>Thanks
>Scott
it doesn't sound like you have checked for error codes. it is easy to do with a piece of wire and cheap circuit tester. go to that dalidesign web site; they have easy to follow instructions. once you get the codes you will know where to start looking. i thought it might be hard to read your own codes without a scanner but it isn't. if i figured it out you can too! if one of your sensors is pooched it will give you the error code.
let us know how it goes.
Rusty,
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Senior User
Joined: Feb 2002
Posts: 402
Likes: 0
Poor MPG
If you pull the sensor out and check it cold the voltage should be around .1.Heat the sensor with a small propane torch and the voltage should come up to around .8 range.Make sure you have the right kind of voltmeter(made for auto use)some voltmeters can damage sensors.
Billy
Billy
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Tuned
Joined: Apr 2000
Posts: 393
Likes: 3
From: Merrill
Poor MPG
I checked the codes there are no codes in the system. He is going to have the cat checked out in the next few days. I guess this isn't as common of a problem as I thought it was.
Thanks for all your help
Scott
Thanks for all your help
Scott
Senior User
Joined: Apr 2002
Posts: 467
Likes: 0
From: On the farm near Loveland
Poor MPG
Hey, Scott, on a late EFI engine I've found that insufficient ignition advance can really kill your gas mileage before you notice performance issues. In addition to all the other good ideas, you might want to check your timing, keep it advanced almost up to the ping point for the gas you use. Make sure the distributor didn't slip.
Good luck!
Good luck!
