Ask HN: Is your ICE car getting less MPG lately?
Ever since the cost of gasoline has skyrocketed, my Toyota has gone from ~30 to ~23 miles per gallon. Engine running fine, spark plugs and air filter are good. Have you experienced this also?
Extrapolating your sample of 1 to the population mpg and assuming a correlation with the fuel price change is as relevant as making a correlation with the horoscope predictions of the month. There are so many things that could change that reading that you’re not telling us that this post is pretty useless.
It would be more useful to try to troubleshoot your mpg change.
I have heard various anecdotal stories of people seeing a drop in MPG, although I would only expect it to be about 3-5% as that’s how much less energy there is in the fuel.
Some older cars aren’t fully compatible with E10, maybe that could be the problem?
It could be costing the equivalent of $1/mile for fuel alone within a couple of months.
Asking because I’m curious…
It’s a total mess
For example, 7 litres / 100km = 0.07 mm^2
It's the cross-section of a noodle of fuel laid out along the road that the car needs without a gas tank.
For example, while we in the UK we still habitually use imperial measures to weigh ourselves rather than metric, we don't know our weight in pounds, but in stones and pounds, which gives a more manageable/comparable number.
It's so habitual to do that, that many people (including me) can't easily do the mental maths conversion to a US-style imperial weight at all.
It still enrages me that there are 14 pounds in a stone but 16 ounces in a pound. What kind of system of logic is that?
Every now and then for personal purposes I think about pence per mile (to compare with e.g. the bus or whatever). My car is about 15p per mile in purely fuel costs by that metric.
If it doubles, then yeah, we're screwed.
To be fair though I guess a lot of people own fancy new cars and so they're already paying more than 45p/mile due to depreciation alone
At say 30mpg (city driving) isn't that 37p per mile?
Unless you're prepared to write off the share of running costs, MOT, tires, insurance which costs a fortune, and is all intended to be covered by the 45p per mile, is it not? All of which could rise by 8% this year (inflation prediction).
As far as I remember reading, most people would already be subsidising once the fuel part reaches about 28-30p per mile.
From what I can tell, very few people in the UK have done the maths as to what is coming for cost of living in the next few months. If the government does not do more than the pathetic measures they have already announced, there will be riots. It is going to be bad on a scale that a person of the median age is too young to remember.
How dirty are the injectors, how clean are the air filter, how good are the spark plugs, if the mass air flow sensor works OK, and some other parts that could make your car to use more gas. All of this can be inspected by any good mechanic easily.
In my area there are 2 types of gas stations - ones with Ethanol and ones that target motorcycle advertising "100% gas" which is more expensive, but you definitely get more MPG. If I were you I'd try a different brand for a few fill ups and chart the differences.
I remember when ethanol fuel came out.
* I no longer needed to run premium in it unless it was really hot outside, plus was fine.
* I actually get better highway mileage with the ethanol fuel.
* It warms up better / faster when it's cold if I run regular.
Someone else in this thread mentioned having the gas tested and that could be possible but i would consider it unlikely.
If you’ve checked spark and air filters, my next questions would be transmission and tires. Are your tires at the proper air pressure? Is your transmission slipping at all? Are your plugs fouled at all?
You could ask a dealership to run a diagnostic, Toyota’s dealership technicians are actually pretty good.
https://www.bellperformance.com/blog/bid/49483/fuel-mileage-....
But while I'm thinking of it, has anyone had any issues leaving a wifi or bluetooth obd2 gadget plugged in all the time? I'm thinking of doing a thing with the nearest bored raspi I find but I'll need continuous obd2 sourced data.
Think in terms of recording / graphing etc.
Winter tires are less efficient.
Winter diesel is supposedly less efficient - gasoline I believe also changes formulas in the winter in some places.
Does a warm car run more efficiently than a cold car? I think so, and mine takes many minutes to get up to operating temperature. On a short trip, I may never get there.