MPG decreasing over time?

[dysert]

I have a new 2014 Fusion Hybrid, and when I first got it (a couple of months ago) I was delighted to see that it was getting about 44.x MPG. I've got about 4K miles on it now, and the last few fillups I've only been averaging around 38-39 MPG. Is it normal for the Hybrid to get worse mileage after it's "broken in"? Or do you think I may be reverting back to my old (bad) driving habits?

[SteveB_TX]

Yep. Ye 'ol lead foot has returned! ;) You don't mention in your profile where you live, so might we assume you live in a region that gets cold? If so, expect your MPG to go down in the winter months as the ICE has to run more to keep your lead foot toasty! :)

[dysert]

Yep. Ye 'ol lead foot has returned! ;) You don't mention in your profile where you live, so might we assume you live in a region that gets cold? If so, expect your MPG to go down in the winter months as the ICE has to run more to keep your lead foot toasty! :)

Unfortunately, I bet you're right. I live around Indianapolis, and it's been getting colder the past few weeks. (Last night we got our first accumulation of snow.) And my old habits have probably returned. I'll go with that since I don't want to think it's the car ;-) Thanks.

[acdii]

Winter blend fuel is most likely the culprit too. I noticed a slight decrease in MPG the past two tanks, and performance on ICE has been a tad under normal.

[hermans]

Mine has gone down a couple of tenths the last couple of weeks. Same # of miles...same routes....same driver and driving style....yep its the colder weather. This is the same pattern as last winter.

[dysert]

Mine has gone down a couple of tenths the last couple of weeks. Same # of miles...same routes....same driver and driving style....yep its the colder weather. This is the same pattern as last winter.

Couple of tenths?! I wouldn't have even bothered to write if that was all. No, I've dropped from 44 to 38-39. I'll just try to drive more carefully and be aware that the cold is not my friend.

[LEM]

Cold weather affects a lot. Even if you freeze yourself to death inside the car by not turning on the heater or the heated seats, it will still affect your MPG.

For me, October is the best month. Not hot and not cold. Last year and this one I got the best mileage.

 

On the other hand, my car has 1 year and 5 months and I haven't seen any changes at all after the "break-in" period. I always got the same mileage.

Edited November 17, 2014 by LEM

[md13ffhguy]

Mine has gone down a couple of tenths the last couple of weeks.

Couple of tenths?! I wouldn't have even bothered to write if that was all. No, I've dropped from 44 to 38-39.

hermans is likely referring to his long-term average. I'm seeing about a 4 mpg decrease over my last tank and a half. Fortunately, this has yet to cause my lifetime average to drop even a tenth.... but it's coming.

[acdii]

With this latest cold snap mine dropped from near 43 down to mid 40. A couple trips returned only 35-38 MPG due to a strong head wind. When I first got the new tires I reset everything except the lifetime summary, so a fresh start on the new tires doesn't look good at all, but its all due to this crappy weather. I had 1 day where temps were good, traffic light and no rain, and that day I got really good MPG, so I know the tires are doing good.