Poor gas mileage until restart, possible causes?

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Tee Celly

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Guys, have a weird problem that just started. 2012 Expedition Limited 177k mostly hwy miles, very well maintained. Usually gets 16 hwy and 12.5 city average.

I drive between Texas cities for work and last couple weeks Ive noticed the hwy mileage had gone down quite a bit, so started watching it. From cold, it will run only 13 mpg on the highway for an hour or so...or until I stop and restart the engine. At which time the mpg will rebound to 15 or so...which is still less than what it used to be, but better than 13!

No error codes , pending or otherwise. From some web reading I suspect maybe a sticking EGR valve? Or perhaps have the tranny looked at? (unlikely, but)

Suggestions are very welcome at this point. Not going to the stealership!

Thanks in advance.

T
 

Plati

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No idea. But I have noticed on my 2014EL 5.4, get better gas mileage once I've driven an hour or so or whatever amount of time. Goes from 15ish to 17.2ish.
 
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Tee Celly

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Sounds like you are using the lie o meter.

Who are you talking about?

If you dont have something constructive to say...go be a pucker somewhere else.

@ Mr Sticker, You can get 17 mpg in these...if you drive 60 mph. Texas is too big for that! lol.
 

Plati

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Who are you talking about?

If you dont have something constructive to say...go be a pucker somewhere else.

@ Mr Sticker, You can get 17 mpg in these...if you drive 60 mph. Texas is too big for that! lol.
Naaa. He's ok I think he means the computer generated MPG display.
A lot of people say its not accurate. I dunno. I think its pretty accurate though.

I just got 17.2 on ~3000 mile drive... interstates were 70mph.

Regarding the accuracy of the Lie-o-meter (on my 2014EL). On a long trip averaging 70 mph on the interstate with some city driving. It reports 17.2mpg typically. If I fill the tank it says 540 miles until empty. I might drive about 470 miles and put in 28 gallons to fill up again. That's 16.8mpg which is about right since its just a rough estimate and fairly close to the reported 17.2. That's just my vehicle, sample of one.
 
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Blksmk

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Who are you talking about?

If you dont have something constructive to say...go be a pucker somewhere else.

@ Mr Sticker, You can get 17 mpg in these...if you drive 60 mph. Texas is too big for that! lol.

Was talking about the onboard computer display aka the lie o meter. But hey... it's ok to get offended over absolutely nothing.
 

Blksmk

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Naaa. He's ok I think he means the computer generated MPG display.
A lot of people say its not accurate. I dunno. I think its pretty accurate though.

I just got 17.2 on ~3000 mile drive... interstates were 70mph.

07, 5.4 el @ 65 mph 23.65 mpg
 

Plati

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07, 5.4 el @ 65 mph 23.65 mpg
For real? Over an extended period? Certainly not doubting your honesty but <skeptical> & I am jealous as He-double hockeysticks. Is that Canadian gallons? Canada uses the British imperial gallon is now defined as exactly 4.54609 litres.

I've had three 5.4 Expys and never got anywhere near that mpg under any driving conditions other than downhill. If you get that kind of mileage you could probably sell it back to Ford and they would reverse Engineer it to discover how it can be!
 
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Blksmk

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For real? Over an extended period? Certainly not doubting your honesty but <skeptical> & I am jealous as He-double hockeysticks. Is that Canadian gallons? Canada uses the British imperial gallon is now defined as exactly 4.54609 litres.

I've had three 5.4 Expys and never got anywhere near that mpg under any driving conditions other than downhill. If you get that kind of mileage you could probably sell it back to Ford and they would reverse Engineer it to discover how it can be!

I'm in the flatlands of Saskatchewan. A few hills mostly valley's, but flat. I got new plugs, coils, battery, upgraded the wiring with bigger gauge wiring s few extra ground to the frame, new headers and 3.25 inch exhaust no cats with a hi flow muffler. I keep my tires at 40 psi and just cruise on the highway at 62 to 65 mph.

My mpg is USA.
 

762mm

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Winter MPG is always worse because of the antifreeze additives they put in the gas (at least up here), plus your engine only gets optimal MPG once it's at full operating temperature.

For a big old V8 like the Triton, that will take a while when the temps outside are freezing. Mine takes a good 10 minutes to get to operating temp and it's still fairly mild outside.


The best time to measure an engine's MPG efficiency is in the summer months. One thing I could suggest right now though is to make sure the MAF sensor is clean and the air filter is in good shape.
 

Rudy Crow

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I'm averaging about 16 mpg on my 15 Expy 3.5 ECO usually driving 75 to 80 on beltway on my way home. Still cant fix the slight shudder.
 

Brent Harward

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There's a lot of variables for better MPG boyz n goilz. ie: Tire pressure, dirty air filter, leaking "T" heater hose on spark plug valley, etc, etc. After kicking around the above I'd wonder into the nearest auto parts joint and purchase 4 cans of injector/carb cleaner, install, and then go for a nice hour of driving at freeway speeds. Betcha gonna see some changes unless the tranny is slipping. But don't bet on anything near 23.65! LOL
 

Plati

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07, 5.4 el @ 65 mph 23.65 mpg
I drove TransCanada 1 east to west through Sasquatchewan 2 summers ago. Never saw so many rolls of hay in my life!!! Millions of them. They even grow that stuff in the median and side of highway. Must feed a lot of cattle. Never saw one cop car the entire trip. I don't think there's a lot of crime up there. Nice country.

Is it worth going back there and going north of TC1?
Bet theres some good fishing and camping up there.

Heres some fresh rainbow trout from Alberta this summer …
IMG_0997.JPG
 

762mm

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I drove TransCanada 1 east to west through Sasquatchewan 2 summers ago. Never saw so many rolls of hay in my life!!! Millions of them. They even grow that stuff in the median and side of highway. Must feed a lot of cattle. Never saw one cop car the entire trip. I don't think there's a lot of crime up there. Nice country.

Heres some fresh rainbow trout from Alberta this summer …


Uhmm.... that's a pretty ignorant statement for someone who claims to be an expert on everything related to North American society, especially on Canada and on our customs (you made some pretty smart ass remarks in other threads about "Canadians", remember?).

Yes, there is quite a bit of crime in Canada lately, especially in Alberta ever since they were hit PRETTY FVCKING HARD by progressive "climate change" policies and by our Libtarded federal government refusing to build the pipeline and the imposition of carbon tax, plus not renegotiating transfer payments from Alberta to socialist parasite provinces out East. People are unemployed, unable to pay bills, unable to pay their mortgages and unable to sell their houses because no one will buy. Property taxes in those areas have exploded since all the private business left. 48% of Canadians are now within $200 of financial insolvency...

So much so that there is now a strong push in the Prairies (Alberta, Saskatchewan and Manitoba) to leave this damn "progressive" train wreck of a country... and rightfully so!


This is what happens when your team wins the elections, by the way... the "free shit / climate change" army is pretty unsustainable. ;)


Take a drive through some of the neighborhoods in Edmonton, AB or in places near the abandoned oil fields with your flashy Expedition and you'll soon wish you had a 2nd Amendment right up here...


:rolleyes:


Nice trout, though!
 
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Plati

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Uhmm.... that's a pretty ignorant statement for someone who claims to be an expert on everything related to North American society, especially on Canada and on our customs (you made some pretty smart ass remarks in other threads about "Canadians", remember?).

Yes, there is quite a bit of crime in Canada lately, especially in Alberta ever since they were hit PRETTY FVCKING HARD by progressive "climate change" policies and by our Libtarded federal government refusing to build the pipeline and the imposition of carbon tax, plus not renegotiating transfer payments from Alberta to socialist parasite provinces out East. People are unemployed, unable to pay bills, unable to pay their mortgages and unable to sell their houses because no one will buy. Property taxes in those areas have exploded since all the private business left. 48% of Canadians are now within $200 of financial insolvency...

So much so that there is now a strong push in the Prairies (Alberta, Saskatchewan and Manitoba) to leave this damn "progressive" train wreck of a country... and rightfully so!


This is what happens when your team wins the elections, by the way... the "free shit / climate change" army is pretty unsustainable. ;)


Take a drive through some of the neighborhoods in Edmonton, AB or in places near the abandoned oil fields with your flashy Expedition and you'll soon wish you had a 2nd Amendment right up here...


:rolleyes:


Nice trout, though!
762 mm is a dimension related to spacing between urinals. How appropriate!

2018 CODE: 405.3.1 Water closets, urinals, lavatories and bidets. A water closet, urinal, lavatory or bidet shall not be set closer than 15 inches (381 mm) from its center to any side wall, partition, vanity or other obstruction. Where partitions or other obstructions do not separate adjacent fixtures, or fixtures shall not be set closer than 30 inches (762 mm) center to center between adjacent fixtures. There shall be not less than a 21-inch (533 mm) clearance in front of the a water closet, urinal, lavatory or bidet to any wall, fixture or door. Water closet compartments shall be not less than 30 inches (762 mm) in width and not less than 60 inches (1524 mm) in depth for floor-mounted water closets and not less than 30 inches (762 mm) in width and 56 inches (1422 mm) in depth for wall-hung water closets.
 

762mm

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762 mm is a dimension related to spacing between urinals. How appropriate!

2018 CODE: 405.3.1 Water closets, urinals, lavatories and bidets. A water closet, urinal, lavatory or bidet shall not be set closer than 15 inches (381 mm) from its center to any side wall, partition, vanity or other obstruction. Where partitions or other obstructions do not separate adjacent fixtures, or fixtures shall not be set closer than 30 inches (762 mm) center to center between adjacent fixtures. There shall be not less than a 21-inch (533 mm) clearance in front of the a water closet, urinal, lavatory or bidet to any wall, fixture or door. Water closet compartments shall be not less than 30 inches (762 mm) in width and not less than 60 inches (1524 mm) in depth for floor-mounted water closets and not less than 30 inches (762 mm) in width and 56 inches (1422 mm) in depth for wall-hung water closets.


Since all you can respond is about the ******* implements you spent your life on installing, I'll take it that I won the argument.

Typical Leftist : lose an argument, respond with ad hominem attacks. Bravo, MrStereotype!

:facepalm:
 
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