Anyone else notice thier fuel economy drop in the winter?
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Anyone else notice thier fuel economy drop in the winter?
Not really. But not much of a winter tho..
I swear I actually got better mileage the other day. ( drove the speed limit due to vertigo lol)
Mine is horrible since i put the snow tires on...I don't think the temps have been bad enough, and road conditions aren't bad enough to have a real bad drop at this point. come Feb, Mar they likely will.
Still not complaining really...think i'm averaging around 7.5 for the winter months. maybe 7.75...
my previous car averaged 10.4-10.7 in the summer!
This topic is worth a dedicated thread. Because I'm the resident fuel economy nerd!
There are so many factors that conspire against winter vs. summer MPG:
1) Winter fuel blend has less energy density that summer blend.
2) Engine takes longer to warm up. This means a richer air/fuel mixture for longer. It also cools off faster, so you're doing more cold starts in multiple daily trips than in the summer.
3) Auto trans holds higher engine RPM for longer. The car won't shift into top gear until a certain operating temperature, which kills economy.
4) You're not idling to warm up are you? :D That's infinity L/100 km / zero MPG and it kills your average.
5) Higher accessory use due to the cold & dark: eg. fan/defrost/full lights
6) Higher average lubricant viscosity: engine oil thickens as it cools. So does transmission and differential fluids and even bearing grease. Significantly more energy is needed to overcome the added drag these cold lubricants cause.
7) Increased rolling resistance from: cold; possibly from your type of snow tires
7.5) Also ridiculous resistance from that snowy/slushy stuff on the road.
8) Lower tire pressure: related to the above... you know your tire pressure drops in step with ambient, right? I see a LOT of obviously low tires on cars when the weather turns cold.
9) Higher aerodynamic drag: aerodynamic drag is proportional to air density, and air density increases as temperature drops. For every 10 degree F drop in temperature, aerodynamic drag increases by 2%
10) Snow/ice on the car: added weight AND worse aerodynamics! Did you clean the snow off your roof? :D Sure you did.
There may be even more reasons than these. Some of them have a small impact, and some of them are big. Added together, it's not unusual for the average person to see a 20% drop in winter fuel economy.
All very logical reasons! Thank you metro.
For me, fuel economy got worse because gas is so much cheaper. I love rippin' it, but I think I'm still getting far better fuel economy than I deserve.
Why is the fuel economy of an automobile worse in the winter than in the summer?
Harold Schock, professor of mechanical engineering and the director of the Automotive Research Experiment Station at Michigan State University, explains.
Simple: all the fun in empty parking lots! :D
HA! Handbrakes are fun!
For sure. I keep forgetting to shut my TC off, so you get that nice rally drift (skid) going and the micra says... "NOPE." Good to know that it works...
Oh, Also. The A/C kicks on when the defrost is running. Might have a bearing on it.
Excellent point about A/C and defrost! We already know A/C drag has a measurable impact on fuel economy.
Thread: AC vs. MPG: impact of air conditioning on fuel economy tested
I've had the stability control kick in just as I feel the car starting to slide on an ice-covered highway transfer ramp at a cloverleaf that I took a little too fast; it's sort of an "Oh, ****...oh, good" feeling as the car starts to lose, and then regains control. Watching other less-equipped cars spin out and crash into the guard rail around me was very surreal.Quote:
Originally Posted by Howie
My only experience with the Micra's stability control was on a rural highway covered with frogs. It works!
I'll just leave that there.
that sounds....ominous....Quote:
Originally Posted by MetroMPG
poor frogger
There were hundreds of them on this highway for a good stretch. It was very strange. (And slippery.)
Why did the frog cross the road???
"There were hundreds of them on this highway for a good stretch. It was very strange. (And slippery.)"
frog corpses do make roads better lubricated, i agree.
I can only hope you didn't do an e-brake slide...but then again, perhaps the Micra was in the mood for some frog sushi:Quote:
Originally Posted by MetroMPG
https://www.youtube.com/watch?v=X_NW2A9D-tw
This is likely a huge issue for me, since I'm always starting and stopping my vehicle between patient visits. Sometimes I'm in their homes for 30+ minutes.Quote:
Originally Posted by MetroMPG