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Coasting with the engine off

I have a new car (RAV 4, automatic). I live 6 miles up a steep canyon. Coming down the canyon I never have to put my foot on the gas. Would it be dangerous to turn the engine off (I still have control over the power steering and brakes) and coast to save gas?

Very dangerous and foolish!

This practice is illegal in some states nad for a good reason.

The amount of gas you would save would be negligible, and you would lose the braking power of the engine, which would result in more wear on the brakes.

Extremely dangerous. Your power brakes have one - two pumps and then become manual brakes and really bad ones at that. Also all the safety systems are shut off with engine shutdown that can save you.

turn the engine off…I still have control over the power steering

Yeah, right. Have you really put ANY thought into this?

No, you DON’T still have control over the power steering (unless it’s electric) and brakes. Danger, Will Robinson! Besides, the extra wear and tear on the starter would probably be more than any potential fuel savings. At idle, the engine uses very little fuel.

There are some lubication components on your car that need the engine running. Not a good idea.

If you coast in gear with the engine running, the computer will deliver minimum fuel to the injectors.
Try to calculate the amount of gas you save by shutting down. It is likely to be pennies per month, maybe less. Leaving aside any risk or damage to the transmission by coasting with the engine off, you should still see that there is insignificant fuel savings. Not worth it.

Did you ever read about people who started out on a trip and were not seen again until a hunter or hiker just happened to spot the car a year later? Some of them may have tried something like you want to try. If you absolutely have to try it, I don’t have any idea what to say to keep you and other drivers safe. I’m still alive but that was just being lucky. I stopped before crossing a puddle at midnight in the rain. I rolled the window down and put my head out to see better and it turned out to be a 200 foot wide gravel pit. To get this into your reality, if a cow walks out in front of you; will all your cars systems be ready to keep you from crashing? I don’t know. Antilock brakes? Any brakes? Good luck.

everyone has good points, and I agree.

Off topic, however, with a hybrid car there are many times when the engine is turned off. I don’t know which (if any) of the hybrid variants do this, but a hybrid could be coasting down a hill with the engine turned off. Steering and brakes are electric, and regenerative braking keeps your speed under control while recharging the battery.

True, but the hybrid vehicles were designed for the engine to automatically turn off only at certain times (mainly when stopped in traffic.) I can guarantee going down a canyon is not one of those times, and certainly not with a RAV4.

This is one of the best examples I have ever seen of being “penny wise and dollar foolish”. The pennies that would be saved in gas consumption will be more than overwhelmed by the extra wear and tear on the starter and the lack of lubrication to part of the transmission.

And, then, when you factor in the safety issue of having NO POWER ASSIST for the brakes and the steering, it becomes just plain foolish to even consider this.

Called Oklahoma Overdrive back in the day. And back in the day, a lot of “Okies” ended up over the side. Of course in those days it was manual tranny. And the engines were not turned off, the car was just put into neutral.

Dangerous, yes. Stupid, yes. Having said that, I leave the car running but still put my MANUAL tranny into neutral on downhill runs that I am VERY familiar with. Saves me, maybe $2 in a year, but makes my old Okie roots feel better.

Sounds like something “Dennis Weaver” would do to get away from a The Tractor Trailor Rig that tried to run his Dodge/Plymouth Aspin over.

There is a rental movie called “The Darwin Awards”. Strongly recommend it.

Does Oklahoma actually have hills long and steep enough to be dangerous to coast down?
I do it all the time but our hills in Texas, (Baja Oklahoma) are mostly just steep enough to maintain the speed limit and I have a manual transmission. Since the owner’s manual ok’s dinghy towing behind a RV with the transmission in neutral, I figure it’s ok when gravity is doing the towing.

Don’t really know about “Real Oklahoma,” since I haven’t been there since I was 4. I am mostly going off “family history” and what I have read from John Steinbeck. But here in Oregon, we have plenty of Hills, which in other parts would probably be called mountains.

I have seen it here on Car Talk that modern engines cut off the fuel while coasting. If that is true, then you will save little money. Coasting in neutral down a hill in gear will eliminate engine braking but you will never get rich for doing this. Try it both ways and send in your findings. You might help to eliminate some controversy.

By the way, coasting down hills in neutral is called “Georgia Overdrive”. How could it be “Oklahoma overdrive”? Driving through Oklahoma from Texas to OK City and then NE to Missouri, I did not see a hill. Does Oklahoma have a hill?

I think the term actually originated in California, when all the California authorities had to deal with all the wrecks caused by the Dust Bowl “Okies” trying to coast down the California hills to save a few cents.

Now, those folks I can understand trying to save a few cents.

These kind of stupid saving techniques are being promoted by people like this guy (“Hypermilers”):