98 intrigue..winter vs summer fuel consumption

My 98 intrigue has 200,000km on it. I have owned the car since 140,000km. I have had very good luck with the car so far.For as long as i can remember the fuel consumption in the winter is drastically worse than in the summer. I can see it being somewhat worse but this seems like almost twice as bad in the winter. The amount of consumption seems to be directly linked with the outside temperature drop and rise.
I live in Canada and most of our winter months are very cold.
Would this fuel consumption issue be related to the air temp. that is coming into the fuel air mixture? If so what can be done about it? Or..do i have another issue. It seems to me, if i remember correctly, the first year i had the car, this was not an issue.
The cel. is out. I do regular maintenance...new wires and plug not long ago. The car runs like a top.

I've wondered the same thing. Some of my families cars seem to be affected worse than others by cold temps.

Other than engine oil & bearing grease thickening, reduced tire air pressure, maybe snow left on the car creating more drag, throw in some idle warm up time if you start it up & run back inside to pour your coffee for 5-10 mins., cold causing less pliability in the tires, snow on the road creates more drag, (I'm stretching a bit now) which all seem fairly insignificant.

Considering that an engine is more efficient when pulling in cooler air & most likely reduced speed due to poor road conditions to offset the negatives, why does MPG suffer in the cold on a properly maintained/running car? Colder spark maybe? Condensation under the hood causing wires that are ok in the summer to leak?

I know/think that if you make a lot of short trips your MPG will suffer more than usual in cold temps as some of the above don't get a chance to warm up.

What weight/type of engine oil are you using? You mentioned well maintained so I won't ask about oil change frequency or thermostat. Old oil is more badder in cold temps...:) Where's your temp gauge?

Glad I could help...lol:)

I use a good quality sythetic oil and it is changed often (10-30)
I doubt it could be all of the above mentions....this is a rather drastic change from summer to winter....she really drinks. I keep the tires checked often due to winter driving etc. I do understand that a car should use a bit more in winter...but not this much. I remember when i was a younger lad....all my cars were never this much different.

My 2001 has big swings as well, like 4-5 mpg. I tend to drive less and shorter distances, which reduces my highway cruising amounts, and then the usual drag related stuff as well. The transmission also is more reluctant to drop into 4th gear, or lockup in 4th, until it is properly warmed, which is usually only halfway through most of my trips. Gasoline also has a winter blend I know, couldn't tell you exactly how it affects mileage but it must have reduced energy content.

I'm with you on this year though, my averages are noticeably lower this year than last year, changes with the temp swings too as I've gotten a couple mpg better the past week due to above freezing weather. In Michigan it did get much colder a month earlier than in the past few years. How are your local temps for winter comparing with last year? I wouldn't be surprised if you had the same thing, got colder earlier and its taken its toll. Also watch your tach religiously when you're puttering around, I'm not sure everyone's transmission has cold reluctance like mine, but I would not be surprised.

oh i'm definatly with you on that one....i cant help but think in the winter months "where the F@#K did my gas go?".....it has to do with requiring more fuel to run in the cold...similar to a choke on an older car or any gas engine (snowblower, snowmobile etc...)...if you let the car warm up for a good 5-10 minutes at least, fuel consumption should be not too much worse than summer....but if you drive your car right away for that first 10 minutes or so (possibly longer because of the cold air passing though the radiator) the fuel consumption is very rich...and doesn't lean out until the temp gauge has hit at least 1/3....but you also have to factor in the gas you burned letting the car warm up...wich makes the savings negligable I think considering the gas price fluctuation I put in about 20-30% more fuel in my car diring the winter than in the summer months.....

Well Ive always heard the fuel itself is less efficient in the winter months. Ive never researched it, but Ive always heard the fuel mixture they put in the tanks is different in the winter months, and whatever is different about it makes it less efficient.

Ive been getting less mileage as well, Ive been getting about 20-21 avg instead of my usual 24ish. But then again theres a possibility I might need an O2 sensor, and who knows what else might be lurking.

ah yeah some states/provinces change their fuel/ethanol ratio in the winter months.....also most pumps say on them "volume corrected to XXXX degrees"...so colder temps mean more fuel at the pumps...so maybe this saves some $$ during the cold weather?

Well if they add more ethanol to the mix that would make it less efficient right off the bat, but I dont know how the mix is adjusted. Ive also heard the whole winter mix thing in states that dont even use ethanol, so there still must be something else.

I assumed i would get an answer that had something to do with a mechanical problem on here. I guess we have no persons regularily contributing from up here in Canada that are very knowledgable or mechanics.
Since my problem is directly associated with the drop and rise in outside temps, i thought this may have something to do with the air coming striaght into the engine via the airbox/filter.
What would happen if i were to somehow get warm air into that air box/filter box. Could i reroute the airbox near the warm exhaust just temperarily to see if it would make a difference?

I cant tell if that last comment had an attitude or not, besides any time I give crap to Canadians they usually just get mad, so Ill leave it alone.


If youre really that concerned about it, you should finish giving the car a tune up, not just plugs and wires.A new PCV valve and most of the time a new O2 sensor are pretty standard items. The O2 sensor has a good sized effect on gas mileage, its recommended to be replaced every 100,000 miles, so if you havent done it, it might not hurt.

Also, what is your tire pressure like? The cold weather will automatically make it lower, so if you havent checked it, its probably low.

and like myself and others have said, it could be something not even related to your cars mechanical condition, such as fuel mixtures or just the fact your car is idling more, or at least I assume it is since most people warm their cars up for a few mins. If you just hop in and drive, your engine is also taking longer to reach operating temperature, which will also make your commute less efficient.

My 2 cents: I always see a drop in fuel efficiency in the winter. Not as dramatic now since everywhere is using 10% ethanol fuel. I have no warning lights on and keep my Intrigue well maintained. I chalk it up to the colder weather.

I normally wait only 15-20 seconds before driving off. All the roads within a mile of my house are 25 MPH zones with a few traffic lights. I use these roads to warm up the cars.

I cant tell if that last comment had an attitude or not, besides any time I give crap to Canadians they usually just get mad, so Ill leave it alone.


If youre really that concerned about it, you should finish giving the car a tune up, not just plugs and wires.A new PCV valve and most of the time a new O2 sensor are pretty standard items. The O2 sensor has a good sized effect on gas mileage, its recommended to be replaced every 100,000 miles, so if you havent done it, it might not hurt.

Also, what is your tire pressure like? The cold weather will automatically make it lower, so if you havent checked it, its probably low.

and like myself and others have said, it could be something not even related to your cars mechanical condition, such as fuel mixtures or just the fact your car is idling more, or at least I assume it is since most people warm their cars up for a few mins. If you just hop in and drive, your engine is also taking longer to reach operating temperature, which will also make your commute less efficient.

My dear friend...that last comment was from ..ME..the starter of this thread.
I was merely stating the fact that there are probably no canadian folks knowledgable that are on here at this present time. I guess i am assuming that you guys in USA never have to deal with the extreme weather tempuratures like we do (-35C)
hence there would be no persons on here from the USA having these extreme gas milage issues.
If you would have read further down the thread you would have noticed that i check my tire pressure regularily.
PCV is fine and checked every time i change oil.
I will think about changing the o2 censor. Can i ask you , why you give crap to Canadians?:disappoin:disappoinThanks

I just checked last night..and yes...my temp. guage does sit somewhat cooler than that of the summer. Other than a winterfront placed on the outside of the car, and/or changing the thermostat, what can be done about this. I am quite sure the themostat is the highest i can get, but i will check my records.

Since the Intrigue has been out of production for a while, I doubt there is any option for thermostat other than OEM spec. If your car is operating at "normal" temperature, I doubt changing the thermostat will help.

You may want to change the O2 sensor since you are seeing such a dramatic drop in fuel efficiency.

Let us know the results.

Since the Intrigue has been out of production for a while, I doubt there is any option for thermostat other than OEM spec. If your car is operating at "normal" temperature, I doubt changing the thermostat will help.

You may want to change the O2 sensor since you are seeing such a dramatic drop in fuel efficiency.

Let us know the results.

I am only seeing a dramatic drop in fuel efficiency in winter. Again...it is directly associated with outside temps. I am not sure that a poor 02 sensor would give me 30mpg in the summer but yet very poor milage in the colder months. A poor 02 sensor would create poor milage winter and summer ..would it not? What they ask for a new 02 sensor up here in Canada is outragous to say the least.....plus..they are not a returnable item. That being said..and the 30+ mpg i get...i think the 02 sensor is fine.

ronnie...i live in canada But I don't see those kinds of extreme temperatures. Where do you live? Coldest this winter was -25 and that was only one night. I live just north of Toronto. Today fwas just above freezing in the sun, and its getting warmer every day...You can try premium fuel as it doesn't usually contain ethanol like regular fuel (up to 10% at most stations)

Harmon, where do you live in Canada? Even in West Michigan, buffeted by the big lake, it gotten down to -20F, almost -30C, a few times this winter. This morning was 5F, -15C for my friends to the north.

Roonie, I believe Hoov is onto something with the fuel-air mix running rich until the engine is warm; I know I try to let my car run until the AIR pump is done doing its thing. Did you ever check your shift points when the tranny is cold to? It sounds like the running rich, higher running speeds due to no lock-up, and a less energy dense winter fuel mix could easily account for the drop in mileage.

southern ontario....in the greater toronto area it gets cold but not the deepest extremes folks even a few hours north can get. must have to do with the lakes

I seem to notice a drastic drop in mileage during the winter months, here in Minnesota, and it only started happening this winter. I got the car last spring and was fine last winter. last winter was a bit more mild than this year. I would think it was because of the cold temps but I am not an expert by any means. Just thought you would like to know that I have the same problem.

most Canadian auto parts stores (napa, carquest, partsource, canadian tire) put a HUGE mark-up on many car parts....fraudulent if you ask me. I always log onto sites like carjunky or 1aauto and order online...about a week later UPS drops the parts off and I save a bunch of money by switching my car insurance to geiko....well maybe not that last part, but definatly save on ordering parts:iceslolan

RockAuto (http://rockauto.com) ships to Canada. Ive always had a pleasant experience with them, as have others here.


And if you go to the last page of this thread, theres a current 5% discount code. That thread is updated regularly as new codes come out.
http://www.fatwallet.com/forums/hot-deals/370308/?start=140

ronnie...i live in canada But I don't see those kinds of extreme temperatures. Where do you live? Coldest this winter was -25 and that was only one night. I live just north of Toronto. Today fwas just above freezing in the sun, and its getting warmer every day...You can try premium fuel as it doesn't usually contain ethanol like regular fuel (up to 10% at most stations)

I live in central Saskatchewan. We have had a terrible winter here with many weeks in a row of -30 temps at night and -25 in the day. This is when my car does the worst.
what would happen if i unhooked my air intake so that i was not bringing in cold air from the front and just brought air in under the hood? Surely my air intake would be warmer...or do i not want to do that? I cant help but thinking how relavent my milage is as the outside tempurature drops.

Your car is going to use more fuel in the winter than in the summer, its as simple as that, and just common sense.


No matter what your approach, your car will take longer to reach operating temperature(max efficiency) in the winter than in the summer. If you let it idle till it warms up, youll use more fuel that way, if you simply get in and drive, it will take longer to warm up than in the summer. I think thats the biggest impact, and why everyone gets worse mileage in the winter, not just you.


As for re-routing your intake I dont think it would be worth it, but thats just my opinion, you might see a performance drop once the vehicle is warmed up as well.

Just make the best of it you can, block off your radiator with some cardboard, that should help your temps keep up when moving. Other than that make sure your tire pressure is high enough, and keep your foot out of the go-pedal until summer gets here.

I have seen some cars were they block the grills in the winter and I don't see a reason for it. Maybe they aren't using 50/50 coolant or they have car issues when the engine gets cold instead of warm when they drive in freezing weather. But this shouldn't be a problem with New Cars etc. The coolant bottle says what the 50/50 can handle. -32 for Dexcool even if its striaght dexcool and u mix 50/50 with a gallon of distilled water. Using 2 coolant bottles to even it out.

I believe that the car only releases coolant from the engine when its warm and pushes it in the radiator again, keeping it warm.

But for best mpg in the winter make sure you to these things
Good tire pressure
5w-30 oil maybe synthetic low vicosity
Tune up
No Check Lights, CEL
Oil change at 3000miles
Idle no more than 5minutes and up to 1 minute after short stops
No more than 2.5 rpm when driving, don't push a cold engine, no rev warm ups.
Good Alignment
Clean airfilter/ PCV

just after Christmas i changed my oil to 0w30 and the engine doesn't seem to turn over so slowly in the cold mornings. Im not worried anymore winter is pretty much circling the drain.....I F@#%ING hate winter