I thought the idea is the colder the air is The denser the oxygen, the better fuel/air ratio. Is it the ethanol added in the winter that is killing my mileage?
I think that you may have missed my point. Although at first glance it appears that you're getting 0 MPG, and the crude MPG meters in some cars will report it as such, the fact is that in a static condition like this, distance (miles) is a constant, not a variable. That means that "M" is always zero while the vehicle is parked. To reduce it further, there is no M in static situations.Yes speed daemon, warming (or cooling) a vehicle without moving WILL contribute to lower MPG. You're burning fuel and not accumulating miles, effectively getting ZERO MPG during that time.
Today we hit a low for the season in Madison. When I went out to pick up a package, my gas mileage was reduced by slippage due to the ice and snow covered pavement, parasitic losses due to the use of 4WD, and an especially long time it took to park in my indoor garage as my windows fogged over. I thought it was interesting that I had to take as long to park as the rest of the trip! But that's an excellent example of how there are many contributing factors to this complex equation.Last week we had negative temps, I didn't significantly change my startup procedure (let it idle the same as normal or a little longer), and I got 2 or 3 MPG less.
The technology for improving cold start performance in automotive engines has improved considerably over the years. Manual choke valves were the least efficient, as you were just guessing how to set them, and could forget to disengage them after the motor was warm. Carbs with bimetal thermostatic controls worked better, but were still crude. Electronic fuel injection was a quantum leap forward, since it could monitor various parameters for best efficiency. And direct injection has all but eliminated the need to enrich the fuel mixture.ever since i dumped the dinosaur that was my 1984 Fifth Avenue for a more modern 1992 Bonneville SSE, my gas mileage has stayed the same in all four seasons. you only notice a drop if you got a old carburetor car that is very cold natured, which dumps gas into it at an alarming rate when cold (as evidenced by the black smoke and carbon stains on snow first thing in the morning).
Ah...the last time I checked, it was the responsibility of the vehicle's operator to make sure that tire pressure is correct regardless of season.you would also be amazed how tire health changes things too. tire pressures drop in colder weather.
Actually richer mixtures create excessive endothermic cooling when the fuel evaporates, which slows the engine's ability to heat the passenger compartment.While EFI may have helped to improve fuel economy, people wanting heat - and wanting it YESTERDAY - as well as the desire to get the engine to optimal running temperature for peak efficiency, calls for the engineers to enrich the mixture to speed up warm up times.
Same thing with mine. Those things aren't precision instruments by a long shot. OK for highway MPG on long trips, but that's about it.I will say this- its MPG counter does seem to factor in idle and stopped time.
Just the sheer mass of the motors tells the story. The old big block V-8 motors weighed in at well over 600 lbs., which is 2-3 times as much mass as the average 4-banger in most new cars. The catalytic converters make a lot of heat too.i never saw any gas guzzler heat up any faster than a modern EFI-equipped car or truck in my experience...
...i think that is due to older cast iron engine blocks in older vehicles, and more newer vehicles have aluminum blocks/heads...
My TDI seems to get significantly lower MPG in the winter than summer... But I stil average 35-37mpg with city driving. I will say this- its MPG counter does seem to factor in idle and stopped time.
We've been tracking upcoming products and ranking the best tech since 2007. Thanks for trusting our opinion: we get rewarded through affiliate links that earn us a commission and we invite you to learn more about us.