Help me with my deteriorating fuel economy

[NEexpat]

Best mileage in the summer, worst mileage in the winter, Canada no less. Sounds like me. I can go 6-8 mpg difference from summer to winter. Let me guess short commutes? You say it's warm now, here in MA. my "cool" engine light is still on in the morning when I get in my car and start it and go.

When I drive out to Ohio, my Ultra-Gauge monitors intake temp, and as I go through western PA at elevation the intake temp will drop sometimes 5-10 degrees and subsequently instant mpg falls off accordingly as the temp drops.

My suggestion when these mileage things come up is ignore the "bars" Go strictly by miles per gallon or liter. Fill it up and go for a 4 hr. drive on a highway, cruise control if you have it and then check your mileage.

Auto or Manual? It may never be getting out of 3rd gear. or only briefly

[nookandcrannycar]

Originally Posted by NEexpat

Best mileage in the summer, worst mileage in the winter, Canada no less. Sounds like me. I can go 6-8 mpg difference from summer to winter. Let me guess short commutes? You say it's warm now, here in MA. my "cool" engine light is still on in the morning when I get in my car and start it and go.

When I drive out to Ohio, my Ultra-Gauge monitors intake temp, and as I go through western PA at elevation the intake temp will drop sometimes 5-10 degrees and subsequently instant mpg falls off accordingly as the temp drops.

definitely a possibility, as you likely have very similar weather to the OP.

My suggestion when these mileage things come up is ignore the "bars" Go strictly by miles per gallon or liter.

If I'm getting really close to empty, I still do pay attention to the bars, but I pay much closer attention to how many miles I've driven on that tank and what my MPG was on the previous tank.

Auto or Manual? It may never be getting out of 3rd gear. or only briefly

Good point. Depending on freeway or surface streets (with signals) and your speed....4th may rarely (or never) see 'the light of day'.