Anyone else notice their gas mileage go to crap as it gets colder? I was consistently getting 17mpg all summer. Now it is fall and cooling off and I'm looking at 14-15. That just doesn't make sense to me. I haven't done the hypertech yet, but I'm guessing the net effect will be the same. Anyone else experience this or have a clue as to why it happens??

 

depending on where your at it could be winter gas.

 

New blends in fuel can cause it, that and a heavier foot from the nice cool air in the intake

 

Winter blends for sure
STEVE

 

Winter gas + temps below 60 = mpg in the crapper

As long as things stay above 60 the drop isn't all that bad for me, but once it dips down low you can forget about it. I'm down about 3 mpg right now.

 

Thank goodness gas prices are coming down!

 

i have a 2001 dak V6 3.9 auto trans, 4.1 gear powr-lok. i moved the intake air sender from the manifold and layed it next to the thermostat. and plug the hole in the manifold, 1/4 NPT i think. my MPG went up 1-2 points. but at top RPM i think it pings a little.

 

Combination of winter blends and cooler denser air charge which commands more fuel. As a bonus you may be making 5 more horsepower with a cost of 2.5 hp per MPG hahaha. And MOE. please put your IAT= Intake Air Temp sensor back in your intake. You are tricking your PCM into thinking your air charge is much hotter than it is which retards the timing and pulls out fuel thus creating a detonation or " pinging". If you didn't know detonation is BAD... like go BOOM kind of bad.

 

Winter blends? Are you kidding me...what is different in the winter that requires a change in the mix of the gas? Or, is this a joke like changing to winter 'air' in your tires? I did put more halogen fluid in my lights for winter...LOL

 

They add more Oxygen to the gas in the winter during refinement of the fuel.
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