Mileage in winter
 

Good morning everyone!

The cold weather and stupid amounts of snow have finally set in here in Calgary and i've noticed a significant dropoff in mileage on my 08 FEH AWD. The dash is telling me 8l/100km however i've watched over the past few days that my fuel gauge is dropping quickly. I've now got half a tank of gas left and i've only done about 200km so far.

I've also noticed that with it being so cold out, the engine revs high pretty much all the time. Doing 30km/h down the icey streets and i'm revving at over 2000rpm whereas it'd only do about 1100 when warmer. I understand that the engine needs to warm up, as well as the battery pack however the day to day driving around the city is emptying my gas tank quickly. It also doesn't go into EV very easily. 45 mins of driving around yesterday and it went in once, for about 2 mins (slow go on Crowchild) at which time the ICE kicked back in and stayed running.

Anyone else experience this or is it time to make a trip into the stealership to get it looked at?

Re: Mileage in winter
 

As Gordon Lightfoot said in a song. "Tis the witch of November come stealin". When pushing through snow and cold any vehicle will expend much more energy. Cold alone seems to stiffen up tires and increase resistance to movement. I have noted at least a 10% drop in fuel economy in standard vehicles simply due to cold. Add 15 cm or more snow and throw away another 10%.

Next is how long you commute or drive each key cycle. My data are from an hour (one way) work commute.

Short drive cycles such as less than 10km do not treat hybrids well in the winter. My mornings are running about -3 C and it will take about 15 minutes before I get the engine off at stop lights. As the temperature drops to -10C that first Auto-Stop may take 25 minutes.

You said AWD. Is it always in all wheel? Other 4X4 hybrids in 4H or even in Auto will give up 5% fuel economy. More in winter just due to sloshing cold oil around in gear boxes.

In general hybrids get short changed on cold short drives.

Re: Mileage in winter
 

My short drive is less than 10km however can sometimes go up to 20km depending on whether I need to bring my best friend to work in the morning.

It is full time AWD, no option to turn it off which I really wish I could do. Its a cold one today and i'm parked in a heated parkade this morning so it'll be interesting to see if it'll go into EV at all on my next 10km haul to home for lunch.

I'll keep an eye on the consumption over the next week as the snow is supposed to stop falling just going to be cold. I'm going to start filling up with some 90 octane shortly in order to prevent fuel line freezing as well as start plugging in the block heater so i'm hopefully not revving as high in order to warm up the engine.

Re: Mileage in winter
 

Will, use your block heater as much as possible. Any octane above 87 will drop your MPG even more. Also, water and snow adds to the weight of the tires and increases roll resistance that decreases MPG. Some people use radiator blocks to keep the engine warm. Learn how to use your brake pedal for regen that will heat your battery faster when it's charging.

GaryG

Re: Mileage in winter
 

Your vehicle is not full time AWD. It is FWD based with the ability to frequently engage and disengage the rear wheels. Some members here have reported on pulling the fuse to prevent the rear wheels from engaging with an improvement in fuel mileage. Some dispute this type of report. Search the forum for details.

Re: Mileage in winter
 

Get a block heater if you don't already have one. I have concluded that it needs several hours to get warm on the block heater. I've moved around to turning it on when I go to bed so it'll be ready & warm in the morning.

Re: Mileage in winter
 

yeah, its cold night and i've just plugged the block heater in. Here's hoping tomorrow goes a little better :D

Re: Mileage in winter
 

It's worthwhile using the block heater year 'round. I get some weird looks about this, living on the lower mainland, but especially for hybrids: getting it warmed up is often mandatory to allowing some or all of the hybrid behaviours.

Re: Mileage in winter
 

Plugged it in last night and although I got heat out of it right away, EV didnt happen. I usually drive in L so I can use the regen engine braking however with it being as cold as it is, that didnt happen. Let my foot off the gas and it just coasted, no regen at all. Also, using the brake regen didn't happen either and instead the engine spins up to burn off the power.

Guess its good to know that the fuel savings I experience in the summer are nullified in the winter :/

Re: Mileage in winter
 

HV battery management is important to get the best MPG. In cold weather, the more you work the battery the faster it heats up. During a cold start you need to start out with as low of a SoC as possible so try to drain the battery in EV before parking. The built-in warm-up strategy will allow your battery to drop as low as 32% if you drive with a light foot. A low battery SoC charges faster and heats-up quicker. Do not drive in "L" because the combination of MG1 and regen is too much charging with a cold battery and you need to slowly give what the battery will take as it warms up. I use a light brake pedal during my warm-up P&G technique to get the battery warm and once it's warm, I'm good for the drive using EV.

BTW, many hypermilers use a block heater year round up north. I don't have one myself but I maximizes the warm-up strategy during all cold starts.

GaryG