Winter vs. Summer running

Why does my car drive better and faster in the winter than the summer? In the winter my gas mileage is terrible, though. And in the summer it pings and feels sluggish like it doesn’t want to accelerate. I live in Ohio where high temperatures range from the 80s in the summer to the 20s in winter.

Is there anything I can do to get better performance in the summer and better gas mileage in the winter?

The pro’s are going to want make and year mileage ect. :slight_smile:

I believe the pinging to be a timing issue

Vehicle/Make and year??

2003 Mazda Protege 5, with 2.0 L4

Sounds like a problem with the engine, a sensor, or maybe some kind of a vacuum leak. You’ll want a mechanic to go over it, see if any codes are stored, that kind of thing.

I very seldom suggest this, but unless you are already at the high end of recommended octane fuel, I suggest you move up.

The fuel is different in the winter and summer. That may be part of your problem.

That will not take care of all of it, because winter blend fuels are (and should be) different than summer blends.  You will loose mileage in winter due to the different fuel and temperatures. 

 However you should tell us what kind of mileage you are getting that you so far only identified as terrible.  It would also be good if you told us what kind of mileage you are usually getting during the summer.  

  Also consider that your driving habits often change in the winter.  We tend to make more short trips and leave the engine idle longer.  

  Finally how are you measuring your mileage.  Are you doing the math (miles divided by gallons) or are you trusting an onboard computer?

I am just guessing, but if you are running your air conditioner in the summer, it will slow down a little car like the Mazda Protege. When you stop running the a/c in the winter, it makes the car seem a lot more powerful.

I would check to see if this engine has an EGR valve and a knock sensor, and see if they are both working right. If they are in good shape, like Joseph says, using higher octane fuel might ease the pinging. Are you it is actually pinging, and not just sluggish because it is running the a/c?

I use 89 octane in the summer thinking it will stop some the pinging and give me better performance, and use 87 in the winter since it seems to run really well on it.

My mileage isn’t figured precisely, but I have a 12 gallon tank. In the summer I can usually get 325 miles out of 10 gallons, but just today I filled up 11 gallons while getting 285 miles out of the previous tankful.

I’ve noticed my winter mileage being a little less than summer in the past, but just recently it’s been more drastic.

And to answer the A/C question from below, I don’t use the A/C much at all.

Generally, cars do run better in the winter. An engine sucks in cool air and shoots out hot air. It’s that temperature difference where the engine gets its power. If for some strange reason there was no temperature difference betwen the air going in and the air shooting out, the engine will stop running. My advice is to use a higher octane rated fuel in the summer. High test gasoline is really a summer fuel, you don’t need it in the winter. Perhaps the reason your gas mileage is worse in winter is because of longer warm-ups.

My guess would b a skewed engine coolan temp sensor.

Cold Air Is More Dense Than Hot Air. Dry Air Is More Dense Than Humid Air. Increasing Air Density Is The Reason For Turbo Chargers And Super Chargers.

All aircraft pilots know this. The difference in aircraft performance between summer and winter (or take-offs considerably above sea level and those near sea level) is even more dramatic than in a car. Not only is the engine performance improved (winter), but also the propeller and wings become more efficient. There have been many fatal aircraft accidents involving pilots who have forgotten or disregarded these facts.

Air density (temperature / humidity / elevation), aircraft load - fuel, passengers, luggage being equal, are all very deliberately computed by pilots prior to flight. Aircraft performance differences from these factors can be huge.

I recently commented about putting on all the clothes I owned and going for a winter motorcycle ride, as a teenager, just to feel the improved acceleration and exhilaration. That cold, dry air made all the difference.


Who does the what now? The temp “difference” has nothing to do with it. The colder air is denser, allowing more O2 and more fuel to combust in the cold weather. However, in winter, the fuel has less energy per volume since more ethanol is added to “winter formulated” gas to reduce cold-weather induced emissions. This may also be helping with the pinging, not sure what ethanol does to the octane rating.

Try 91/92 in the summer, just to see if it helps. It could be carbon build up causing pre-ignition, or just a high compression engine. I am not familiar with the Mazda engines

jmcarc—wow… just… wow… you have no idea how an internal combustion engine works AT all, do you?

I know enough to keep my 212000 mile Buick running. Plus, I have an engineering degree.

What kind of engineering degree?

Knowing enough to keep your 121,000 mile Buick running means, at minimum, you know how and when to pay someone to do the maintenance. You don’t have to understand how an engine works to keep a car running for a long time.