# Check engine light **URL:** \ **Category:** Maintenance/Repairs\ **Created:** [January 12, 2016, 2:54am UTC](https://community.cartalk.com/t/check-engine-light/92233 "2016-01-12T02:54:38Z")\ **Posts on this page:** 10\ **Page:** 2
**Author:** ![BillRussell](https://sea1.discourse-cdn.com/cartalk/user_avatar/community.cartalk.com/billrussell/32/3179_2.png) [@BillRussell](https://community.cartalk.com/u/BillRussell)\ **Post date:** [January 22, 2016, 5:11am UTC](https://community.cartalk.com/t/check-engine-light/92233/21 "2016-01-22T05:11:23Z")
Driving habits have a large influence on MPG. Do you accelerate quickly off a green light? wait till the last minute to brake for a red light? Frequently change lanes on highway driving? Drive well above the speed limit? All those will reduce MPG. Cold weather also reduces it. I can measure 34 MPG on a 50 mile trip I take frequently, mostly highway. But if it’s raining or snow and I slow down from 70 to 50 MPH, the MPG jumps up to 40. And in the winter it drops to 29. ---
**Author:** ![byline](https://sea1.discourse-cdn.com/cartalk/user_avatar/community.cartalk.com/byline/32/1554_2.png) [@byline](https://community.cartalk.com/u/byline)\ **Post date:** [January 22, 2016, 6:54pm UTC](https://community.cartalk.com/t/check-engine-light/92233/22 "2016-01-22T18:54:47Z")
Both of us are pretty good drivers in that regard. We brake well ahead of a red light, don’t accelerate quickly when it turns green. I prefer to stay in the same lane whenever possible. I guess you could say I’m a very cautious driver, and I do most of the driving for this vehicle. We also put winter tires on, and I know that reduces fuel efficiency. However, when I say that 29 MPG is our maximum, that’s during the summer, and also during mostly highway driving. ---
**Author:** ![byline](https://sea1.discourse-cdn.com/cartalk/user_avatar/community.cartalk.com/byline/32/1554_2.png) [@byline](https://community.cartalk.com/u/byline)\ **Post date:** [January 27, 2016, 6:44pm UTC](https://community.cartalk.com/t/check-engine-light/92233/23 "2016-01-27T18:44:12Z")
Something I just thought of, which will affect our fuel efficiency: Where we live there’s no such thing as a flat straightaway. All our highways and roads are near the ocean, with lots of steep hills and curves. So that probably explains why we’re not getting the EPA-rated MPG. ---
**Author:** ![Yosemite](https://sea1.discourse-cdn.com/cartalk/user_avatar/community.cartalk.com/yosemite/32/643_2.png) [@Yosemite](https://community.cartalk.com/u/Yosemite)\ **Post date:** [January 27, 2016, 8:31pm UTC](https://community.cartalk.com/t/check-engine-light/92233/24 "2016-01-27T20:31:35Z")
The hills and curves would certainly make a big difference in your MPG with any car. Post back when you have the dealer replace the part in question. It may help someone with this particular problem on a latter day. Yosemite ---
**Author:** ![byline](https://sea1.discourse-cdn.com/cartalk/user_avatar/community.cartalk.com/byline/32/1554_2.png) [@byline](https://community.cartalk.com/u/byline)\ **Post date:** [February 3, 2016, 11:22pm UTC](https://community.cartalk.com/t/check-engine-light/92233/25 "2016-02-03T23:22:23Z")
Thanks, Yosemite! I just scheduled an appointment for next Tuesday, so I will post an update after that. By the way, we took a trip last weekend, mostly highway driving, but with steep hills and curves that are part of the territory around here. Heading down into the valley, we used the “downhill descent control” feature, which likely affects fuel economy. Plus we are driving on winter tires, and on the way there we drove through a fair bit of snow and slush that hadn’t been cleared away. Still we managed to get 28 MPG, so all things considered that’s probably about as good as it gets with this car. ---
**Author:** ![byline](https://sea1.discourse-cdn.com/cartalk/user_avatar/community.cartalk.com/byline/32/1554_2.png) [@byline](https://community.cartalk.com/u/byline)\ **Post date:** [February 19, 2016, 7:37pm UTC](https://community.cartalk.com/t/check-engine-light/92233/26 "2016-02-19T19:37:35Z")
Sorry to be so late in posting an update. Because of bad weather on my original appointment date, I had to reschedule my appointment for Wednesday. The fuel tank pressure sensor was replaced, and then the mechanic cleared the code and verified the repair. Since then, so far so good. No check engine light! ---
**Author:** ![insightful](https://sea1.discourse-cdn.com/cartalk/user_avatar/community.cartalk.com/insightful/32/2732_2.png) [@insightful](https://community.cartalk.com/u/insightful)\ **Post date:** [February 20, 2016, 7:07am UTC](https://community.cartalk.com/t/check-engine-light/92233/27 "2016-02-20T07:07:46Z")
Thanks for the update; it is appreciated. ---
**Author:** ![byline](https://sea1.discourse-cdn.com/cartalk/user_avatar/community.cartalk.com/byline/32/1554_2.png) [@byline](https://community.cartalk.com/u/byline)\ **Post date:** [February 24, 2016, 2:33am UTC](https://community.cartalk.com/t/check-engine-light/92233/28 "2016-02-24T02:33:08Z")
OK, you know how I mentioned fuel economy before, and how underwhelming it is? Today I filled up the Fusion (remember, this is post-repair). I’d done a fair bit of highway driving between the last fill-up and this one, all driving I’ve done before, and this time the fuel economy was markedly better: 35 mpg. Is there any reason to believe that replacing the fuel tank pressure sensor would cause this to improve? ---
**Author:** ![insightful](https://sea1.discourse-cdn.com/cartalk/user_avatar/community.cartalk.com/insightful/32/2732_2.png) [@insightful](https://community.cartalk.com/u/insightful)\ **Post date:** [February 25, 2016, 3:17am UTC](https://community.cartalk.com/t/check-engine-light/92233/29 "2016-02-25T03:17:37Z")
> _Is there any reason to believe that replacing the fuel tank pressure sensor would cause this to improve?_ No. ---
**Author:** ![byline](https://sea1.discourse-cdn.com/cartalk/user_avatar/community.cartalk.com/byline/32/1554_2.png) [@byline](https://community.cartalk.com/u/byline)\ **Post date:** [February 25, 2016, 6:05pm UTC](https://community.cartalk.com/t/check-engine-light/92233/30 "2016-02-25T18:05:37Z")
I thought so. Hmmm … trying to figure out why this suddenly “optimistic” fuel economy turned up. My mileage and fill-up figures for both entries are correct, so that’s not the problem. [Previous page](https://community.cartalk.com/t/check-engine-light/92233.md?page=1)