Seems like a silly thing to do to potentially save .25 a day if you’re lucky. Plus the wear and tear on the starter, plus the extra wear on the engine–a lot of engine wear occurs at startup. Plus the annoyance to other people, plus the radio, wipers, heat, etc. shutting off with the engine.
Plus if you’re really into being “green”, you’re likely polluting the environment far more with the start/stop than you would be just letting it run—the engine management computer is running in “open” mode for a little while after startup, and not controlling the emissions nearly as well.
For the person that mentioned a pizza gig: I too once had a job like this several lifetimes ago. One night when my starter was going out I left my car idling for a total of over 12 hours… didn’t use more than a quarter tank extra as I recall, and this was a carbureted small V8. Gas was under a buck a gallon then though…
I agree that he shouldn’t be doing this, and that he won’t be saving any money. I disagree that the starter will now fail yearly. Maybe he will only get ten years out of it where he would have got twenty, but he won’t be replacing it every year or two either.
Does turning off engine at red lights save gasoline?
The OP asks about RED LIGHTS plural, and I was talking about other red lights, as well as the one mentioned. You know that if you pull the mirrors in you can save fuel too. Or keep the gas tank near empty, less weight= more mileage.
You may be saving a little gas, but not much. But, I disagree with the comments on the wear on starters. My co. runs delivery vehicles (both cars & pickups) that start & stop much more than a normal car would, & very seldom ever have a starter go out.
Your best bet for saving gas is pratice what I call seamless driving. Adjust your speed so you hit the lights green. So many race from one stoplight to the next; a big waste of fuel. Accelerate gently and drive smarter. You’ll be surprised how fewer stops you’ll have to make, and how many cars that were sitting at the last light, will be sitting at the next red light idling while your hitting it green. You can wave at them as you drive by!
I’d have to disagree with you tardis. I’ve read in several publications that its a common myth that starting a car takes more gas than leaving it running; at the least, its a negligible difference. So, short and simple, stopping your car might put an extra load on the starter, but in the end, you will save gas, and reduce emissions. And I think saving the world one person at a time is worth more than a starter, in my opinion.
EllyEllis, I agree with reducing weight. That junk in the truck probably isn’t all necessary. The empty gas tank and pulling in the side mirrors (for those that can) I can’t support only because the first has other potential side effects (like running out of gas in a bad neighbothood), and folding the rearview mirrors in has obvious safety implications.
Gas savings would most likely not be measurable.
but…
I CANNOT BELIEVE ANYBODY DID NOT MENTION THIS…It’s a good way to get rear ended! People are coming up behind you and they see the light turned green and assume you are starting to take off but the small amount of time it takes to start your car and drop it into D could get you smacked in the can. Remember that these drivers are eating, texting, phoning, make-up-ing, shaving, dancing, nodding off, etc., while they are approaching you.
I believe you cannot simply drive and let others drive. You must drive defensively and never assume the other guy will do the right thing.
Hello Folks, thanks for all the good input. I’ll add that I probably do this two to four times a week, and I’m always careful to be in gear when the light turns green again. And I almost always turn my engine off at ATM machines, unless I’m in a dicey neighborhood.
Bottom line appears to be that I am not saving much.
Yes, by all means drive like someone’s senile aunt regardless of how irritating it is to other drivers and how much it inconveniences anyone but yourself. It’s worth it to save 20 cents a day…
It may save a little gas but the wear and tear on the vehicle is more than the savings. What if your car did not restart? A service call payment can buy a lot of gas.
While I would love to theorize with the rest of the group on the various merits or demerits of this, I am afraid all I can offer is some actual test data…
Using my GPS I discovered that I was spending about 1/3 of my time stopped while driving in the city. I then did a test shutting my engine off at stop lights, when it was safe to do so. If I was the first in line at the light, I did not shut down. However, if there were a few cars ahead of me, I did shut down.
In my Odyssey I was initially getting about 16.5 mpg in city driving. Minimizing the amount of time stopped at idle, my gas mileage rose to 18.2 mpg. The Odyssey burns just under 0.5 gallons per hour at idle.
This saving amounts to a savings of about $6 every time I fill up. Since I usually fill up about twice a month, that would be a savings of $12 per month.
In addition, my computer suggested oil change interval did not change, nor did the results from oil analysis.
Your results will most likely be different, but I think it would be worth testing to find out if you could benefit from shutting things down. In my case, some of the stoplights lasted much longer than 2 minutes.
If you’re paying attention and are ready to go when the light turns green, it’s fine.
A modern fuel-injected engine, when warm (not entirely sure about cold) doesn’t use much fuel to get started. It should just be a matter of seconds before it means you’re saving fuel.
The only down side is wearing your starter/solenoid/ignition switch faster.
Speaking of idiots who race from stoplight to stoplight…you must be one of those I wave at as I drive by. Tell me how it inconveniences you if I’m hitting the lights all green, and your hitting them all red?
Anyone even asking this question is talking about every stop light, not one or two extra cycles a day, and taking the ‘green’ thing way too far.
Who’s gas are you saving and who’s gas are you expending ?
Think of needing that starter in two years that I took ten years to need.
When your starter dies, does it leave you stranded needing a tow truck, expending fuel ? Or do you drive your other car on an otherwise unneccessary trip ( expending fuel ) to the parts store to get one ?
Do you take your car to a mechanic who orders one from the parts store who delivers it in their little ‘how’s my driving’ Ranger , expending fuel ?
Then the parts store orders much more starter inventory delivered by fuel expending trucks.
And the pennies saved on fuel , spent on a starter and labor, balances out in who’s favor ?
Then the parts factory, who now is producing more starters for more fuel savers… is how green in it’s own rite ?
Just save everyone the trouble and be ready to go when the light changes.
( I’ll be glad to sell you a starter, I’m a parts man and you’re my paycheck, come to think of it disregard everything I just told you and bring me $129.99 )
