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Better for engine and environment

In another issue of debate with my father is the issue of turning your car off adn then restarting and such when you are in line at say a drive through, at the bank or such. He says that it’s more wear and tear on the engine to stop and start it and you use more gas then just letting it idle. I contend that if the line is long and you are going to sit for a couple of minutes it is better for the engine the environment and such to shut the car off, then restart and pull up. I especially believe in this when stopped for a long train and such. So what is better for the engine and such?

He’s correct. It’s better to let it idle.

Hybrids are becoming commonplace now that do, in fact, turn the engine on and off, but they’re designed with starter systems that are more robust than the average engine. An expected lifespan for a starter assembly is perhaps 150,000 miles. If you quadruple the amount of usage, the lifespan becomes 1/4 of expected.

Dad’s comment about the gas usage goes back to the days of carburators. Engines today don’t waste additional gas starting…but they don’t waste gas idling for a few minutes either.

By the way, I’m impressed by yuor enquiring mind. If you’d like, post back and I can suggest some reading material on the mechanics of automobiles.

It’s ever so slightly better for the engine to leave it running an extra minute or two, and it’s ever so slightly better for the environment to turn it off for a minute or so.
Of course, to shut it down you have to shift to neutral or park and then back to drive when you restart it, so you are adding minor wear to the transmission and the rest of the drive-train too.
When it’s all said and done, it’s not going to be much difference either way.

Better for the engine (well, for the accessories attached to the engine): Leave it running. As explained, batteries and starters have a roughly finite number of start cycles, and more start/stops=shorter starter/battery life.

Better for the environment: Well, it’s kind of a wash…and it depends on what part of “environmentally correct” matters to you. Shutting it off almost always saves on gas (and CO2), but when started back up, the car’s in “open loop” mode, so richer-running (and more CO, HC). Also, shutting down long enough to let the cat cool off will result in greatly increased emissions until cat warms up again.

Better for your wallet: Leave it running for short stops, shut it off for long ones. The exact “break-even” point will vary depending on the cost of parts and your ability to do the work yourself. I’d think >5min would make shutting down attractive, possibly less if you can DIY.

In your calculations of environmental/financial impact, consider the condition of the car/starter/battery and your ability to guarantee a quick restart. The gas burned (and tow called) by folks stuck behind your stalled car will rapidly destroy any “green” savings (either kind of “green”) from shutting down.

Plan C: I Can Understand Waiting In My Car For A Long Train, But If I Were Concerned About Idling, Restarting, Harming The Environment, Etcetera, I’d Park And Walk Into The Retaurant, Bank, And Such, Especially If I Saw Multiple Vehicles In The Queue.

That’s how I roll and I seize the opportunities for exercise, rather than avoid them. Often this procedure saves time over the idling routine and I don’t have to debate the issue (Plans A & B).


Anything over 30 seconds turn it off. Wear and tear on what? since you don’t know how many starts are in a starter are you going to obsess over every start like it is the last one? The mindset of wearing a starter out from too many starts belongs with the mindset of leaving the lights on in the room because it consumes more energy to “fire them back up” and that place is the dark ages. Once people get this “leave it running” mindset in their brains it is almost impossible to break.

Thanks, oldschool. I agree.

There is no extra wear on the engine from shutting it off and restarting it. How could there possibly be? It’s already warm, and starting the engine doesn’t produce extra wear. I’d argue that shutting it off reduces wear, since there is ZERO wear when the engine is not running.

The starter is another issue, but I believe the starter is designed to start the engine whenever you want it to without damage.

When I’m in a long line, or stopped at a railroad crossing, I shut off my car’s engine to save fuel and reduce pollution.

I seriously doubt that the few times this happens will make a significant difference in the life of my cars’ starters.

I agree with both oldschool and mcparadise.

And, like CSA, I also assess the length of a drive-up line, and if it would take me more than a couple of minutes in that line, I use this as an opportunity to get out of the car, walk into the bank, fast food joint, etc and get a little more exercise.

As to premature starter failure, I have never had to replace a starter in any of my cars, and that includes cars with well over 130k on the odometer.

I also agree with the above.  The hybrid cars generally allow the engine to shut down after a rather short time.  They have extra heavy duty starters so they can easily restart the engine.

If the line is long at the drive-thru, why are you getting in it? Why not park the car and go inside?

I think that the answer is fairly obvious. Most folks nowadays are incredibly lazy.
As evidence of that, take notice of how much heavier the general population is, compared to years ago. Yes, portion sizes have increased, but the amount of walking done by most people is truly minimal, and that makes a difference–in a very negative way.

I think there’s far better ways to save money and the environment than shutting your car off at every slight delay in your life.

For example, if most people (myself included) would pay attention to the food in their fridge and not buy things and throw away part of them because they let them rot, it would not only save more money than any alleged savings, but would be better for the world as well.

I’d rather spend an extra $1 a week and not have the wear n’ tear on my starter, engine, battery, etc., especially in winter. To say nothing of the inconvenience of not having heat, A/C, the instant ability to react in a situation that requires the vehicle to move, etc.

My step dad went out to the White Castle they finally built here in town when it first opened up and commented on all the people there. He said the cars were literally circling the building waiting for the drive-thru, he parked, went in and was out in 5 minutes. The next time he went in, it was a minute or two at most. I have no problem walking into the place rather than wait, nor do I mind walking a bit further at the store or work and park a ways out in the lot.