Cold weather = 10mpg???? Anybody else?

[Former_Jeeper]

So i was getting around 16 mpg, driving habits mostly same, fresh alignment. No check engine light, 84k on engine, yes air filter clean. Yes 5w-30. Yes just cleaned MAF sensor not too long ago. Yes fresh plugs, wires etc.. air pressure 32 psi.

Point is all of a sudden just when the weather started to get colder, (35) i am now getting 160 miles to a tank?

Does anyone else have this experience?

99 3.4L. automatic.

:wtf:

 

[SR5Runner97]

What was the temp when you were getting 16mpg? Because if it was hot 75? then went to freezing. It is possible. Are you letting your car warm up before you get in? That screwed me.

 

[OTB]

What was the temp when you were getting 16mpg? Because if it was hot 75? then went to freezing. It is possible. Are you letting your car warm up before you get in? That screwed me.

Letting a car warm up should not make a 6 mpg difference.

Unless maybe you are starting it before you go to bed at night and letting it warm up over night.

 

[Former_Jeeper]

warm up minimal.

I hope it was just a fluke and that i dont have to fill up every 150 miles.

anyone else think of a culprit/reason?

 

[nissanh]

How many miles you drive each time?
I have the same situation. Doing like 12 or 14 in the city because the town I live in is 2 miles long! It won't even heat up by the time I reach my destination.

 

[M-Piers97]

Its because your a former jeeper and your 4runner does not like that :hiding:

 

[kball]

If your area switched over to winter fuels it might make a 1-2mpg difference but not 6. Check your odometer and make sure it's counting right.

You are basing your mileage on miles AND gallons used right?

 

[Former_Jeeper]

Yes I am basing it on mileage/gal used.

anyways I will do a couple more tank fulls and see what happens.

The only thing that came to mind is i have been adjusting the front adjustable coilovers so that it has no rake and sits mostly level, maybe somehow it changed the aerodynamics enough to make a 6 mpg difference? Maybe it needs just a slight forward "lean" to achieve optimal fuel efficiency?

Anyone have any input on this subject??

 

[snivilous]

Yes I am basing it on mileage/gal used.

anyways I will do a couple more tank fulls and see what happens.

The only thing that came to mind is i have been adjusting the front adjustable coilovers so that it has no rake and sits mostly level, maybe somehow it changed the aerodynamics enough to make a 6 mpg difference? Maybe it needs just a slight forward "lean" to achieve optimal fuel efficiency?

Anyone have any input on this subject??

No, that shouldn't make that much difference. I get 10mpg with a 3" lift and that is at least 50% offroading, otherwise I get 14-16 city.

I don't know why the mileage would drop so much, you could try running some fuel injector cleaner and checking your air filter. Hopefully it's just a fluke.

 

[jeff88]

I think it could be entirely possible, unfortunately. There are just so many variables, if any of them change so does your MPG and with so many it's hard to narrow them down. Winter fuel could be 1 or 2. Colder air has more oxygen which equals more fuel injected. That in itself could be 1 or 2. With that the truck might feel more peppy and you unconsciously drive it a little harder. That could be 1 or 2. You may have driven a little more city then befire, which could drop it down. Even though most people don't like the uneven height of SUVs, the angle helps aerodynamically, which could be 1 or 2. Maintenance issues could cause problems, although it sounds like you're up to date on everything. You didn't mention if you changed your oil recently. With it being cold, you might have oil that is thicker than the same oil during summer, that could cause 1 or 2. Of course, it could just all be because of wind. If you hit a head wind for 100 miles, you're not going to go much farther.

Hope this helps. I think, like you said, try a few more tanks and see what happens. Hopefully it was a fluke and not cause for concern.