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Engine off at RED

I am a member of the ‘engine off at red light’ club, as I have found it to conseve significant gasoline in my town. My question has to do with actions prior to restarting the engine.

Years ago, when cars had distributors containing breaker points, it as generally recomended NOT to turn the key ON for an extended period prior to starting the engine. The given rational was that such action could cause the points to burn and pit.

Today, most cars have individual igniters for each plug, and the points in a distributor are history. Is there any danger to turning the ignition ON for a period prior to starting (or restarting) the engine? This action minimizes the ‘time to start and get moving’ away from a traffic light recently turned green.

Obviously you never drove a car daily with 500,000 miles on it or you wouldn’t be shutting it off at every stop light for fear of it leaving you stranded. On the old cars with the key on it would be running the power through the points just like if it were running, correct. On the new cars it just takes more battery to run all of the accessories, lights, and so on. Don’t you ever get honked at while you waste the fuel of people behind you waiting to go again? I really don’t think you are saving a thing in the long run, or maybe micro-scopically at best. The drain on the battery while sitting there and the battery surge needed for the starter will cause the alternator to work extra to recharge the battery again, thus putting more drag on the engine, thus burning more fuel than it would have otherwise. Don’t you dare sit there at night with your lights off though-big liability to you if anyone hits you. I used to teach the Minnesota “Feather Foot” class on economical driving and never ever would we encourage shutting the engine off unless it were longer than a couple minutes which most stop lights are not.

You’re using your starter way more than it was designed to be used. Make sure to put aside the money you’re saving now (and probably more) to use for replacing your starter if it wears out.

Seems like a pretty pointless endeavor, and if you live in a region where it gets cold, a day with the temp in the single-digits will probably make you change your mind.

Wear and tear on the starter motor, ignition switch, neutral switch, etc with the eventual failing to start because of the failure of one or more of those items is a good reason to leave the car running.
And you’re saving “significant” gasoline by doing this?

You’re wasting fuel, wearing out your starter, and inconveniencing everyone behind you. And if a cop catches you, you will get a ticket. There is literally no good reason to do what you are doing.

I’m with everyone else and @Bing sums it up real well. There are distinct engineering differenses between your truck and a hybrid or “golf cart” designed for such driving behavior. Things like much larger starter motors or starting through an accessory belt allow a hybrid to withstand such abuse. With all due respect, I am always amazed how some people can own a vehicle then pretend the owner’s manual never existed. If what you say works, it would be common practice with all vehicles. If you think traffic lines and new starters are a pain , imagine what it would be like if everyone did this.

One of the things to go after a starter motor and selnoid will be your ignition switch. The dealer will love you and the next owner will really be PO’d. Be sure and mention this if you private sell it. You may get to knock off a significant amount from your asking price.

What you are doing is very inconsiderate for the other drivers around you.
The traffic lights here in the US cycle the following pattern: red - green - yellow - red. This is designed to accommodate the vast majority of automatic transmission cars. On the other hand in the EU the light cycle as follows: red - red and yellow - green - yellow - red. The red and yellow together gives time to the drivers to put manual transmissions in first gear and get ready to take off.
So while you are trying to restart your car -at the green light- you are holding up everybody behind you. I am sort of guilty in this as well because I need some time to put my transmission in first gear and drive off.
So if the lights would use the extra red and yellow step here you would have time to restart your car. On the other hand listen to the others, you are putting extra strain on your starter etc.

Turning off the engine at red lights does save fuel. But it also does wear out the starter motor much faster, your starter wasn’t designed for this type of service. Leaving the key in the on position in a modern car while waiting for a green light doesn’t do any harm, but it doesn’t help either, the car will not start any faster.

If you have a manual transmission, then you can do this without holding up traffic, but if you have an automatic, then you probably are, unless you are watching the lights for the cross traffic and restarting when they turn yellow.

This was tested in Japan where some prototype cars had an automatic starting starter installed. when the car came to a stop, the engine would shut down. When the gas was pressed, the starter would engage and start the engine while still in gear (automatic transmission) and the car would go. This was done back in the 70’s with taxi cabs which meant carbureted cars. It didn’t work well at that time. It saved fuel but reliability suffered.

Some hybrid cars use this technique, but their starter motors are also the drive motors so they are very robust. starting the engine is no strain for them.

I could see doing this in places that typically have very long light cycles. California for example holds the red lights for what seems like at least 2 minutes. Around here, a red light typically will last no more than 45 seconds and could be as little as 15 seconds so shutting down would be a waste of time and effort.

If you really want to save gas, try matching your speed to the light cycles so that you hit every light green, that way you don’t have to stop at all. I do this and I get really good gas mileage around town, about on par with my highway mileage. My brakes and clutch last a really long time too.

The OP didn’t give the year, make, and model of the car he is driving. Assuming it is a late model car, it has electronic ignition, and fuel injection. If you move the key from the “on” position to “ACC” for accessories it will stop the motor. Then just turn the key past “on” to the “start” position to restart. There is no real difference in using the ACC, off, or on position of the ignition switch as far as any damage to the car. The electronic ignition can handle any position without damage. Leaving the car in the “on” position will use a bit more current from the battery, but that shouldn’t really be any big deal.

Whether the practice of engine off on red saves gas or not depends on lots of factors. More start cycles will make the starter motor work more frequently. It might shorten the life of the starter over time. What really kills many starters is overheating when they are used for a long period to start a motor that isn’t running well and takes a lot of cranking to start. A quick start of a warm motor is easy on a starter, but in time the extra use will take a toll on the electric motor and the bendix drive that engages the flywheel.

If I had a starter motor buried deep inside a motor (some new Cadillac motors put the starter in the V under the intake manifold) I certainly won’t recommend killing the motor at every red light. If I lived in North Carolina which seems to have the longest red lights I’ve ever seen, I might kill the motor for known long red lights. But I might just price out the cost of a new starter installed to see if it is worth it.

Yes, give the year, make, model and VIN number so we can avoid this vehical if it goes on the used car market. Ever look into “pricing out” flywheel whose teeth are worn or broken ?

You bought the wrong car. Ford Focus, I believe, has this feature already built into it, no need for driver input, it has a start-stop feature that shuts the engine off automatically; it’s designed the way from the get go.

Driving through North Minneapolis at 1:00 in the morning, no way I’m shutting the car off. In fact I’m looking around ready to peel through the red light if necessary while ducking down to avoid the shrapnal.

Occasionally I will turn my car off at a drive through, but never at a red light.

Often times when I hear the mail car in the area starting the truck over and over from house to house I think of the number of starters each truck goes through, and I wonder when they will get electric cars. For very many routes golf carts are suitable, less noise too.

Dear OP I encourage you to save more gas by converting your car to electric, then your ‘car off at red lights’ will be as simple as taking your foot off the accelerator.

As the others have implied, the OP might actually save 30 or 40 cents per week on his gasoline bill by doing what he is doing. And, over a period of…a few decades…that might actually save enough on gas to pay for the starter that he is wearing-out prematurely.

However, over those decades, he will wear-out several starters, so this is a losing proposition, no matter how you look at it.

Often times when I hear the mail car in the area starting the truck over and over from house to house I think of the number of starters each truck goes through, and I wonder when they will get electric cars. For very many routes golf carts are suitable,

The post office is far better at these things than you might guess. When I worked for them, I often wondered why they were using a procedure that was clearly, to me, to be less efficient. However when I checked, sure enough they were smarter than they appeared. OK it has been a while since I was in the Post office, I would bet they still are doing a great job.


As a former postal employee, I know they were hyper-vigilant about preventing rollaway/runaway incidents…to the point that a letter carrier could get a written reprimand if his vehicle was observed parked without “curbed” wheels.

So, unless there’s been a wholesale attitude change lately, fuel savings is probably a secondary consideration when it comes to shutting down at each stop requiring “dismounting” the vehicle.

There’s another way that the '‘engine off’'ers cause more fuel consumption than they save.
– other people’s gas. –
every single time one of these people sandbags the line of traffic behind them…
someone ( or 2 ) DOESN’T make it through a perfectly good green light which they would have …if only the line of vehicles had begun moving in sync when the light changed for them.
They have to wait AGAIN and idle even more time than if they had gone through when they should have.

If you’re looking at a rush hour line of traffic , just a one time delay of two vehicles missing their turn has a massive ripple effect far further back in the line. ALL of whom are now wasting fuel they would not have but for the do-gooder who can only think of themselves and not co-ordinaet their moves with the dozens of other vehicles on the road too.

The only time ‘‘engine off at red’’ works right is when that person is far enough forward in line to clearly see the changing of the opposing light to be properly ready for their green.

We don’t have this problem in Wash. DC because all the type A personalities are drag racing and cutting each other off when the light turns green.
Nobody wants to chance losing even a few milliseconds.