Hypermiling Newbie!

[Miller88]

Originally Posted by mcrews

THe trick to 'coasting, engine on' is if the rpms drop to idle when in neutral.(imho)
I drove a 2009 Ford Tarus for a couple of weeks a while back and the rpms DIDNOT drop when coasting in neutral.

Fords always seem to idle stupidly high when put in neutral. I kicked my Taurus into neutral once trying to go from D to OD ... with no foot on the gas, the RPMs shot up to 3000 for no reason.

[UltArc]

Engine on coasting, like everyone else said, really matters on the car and conditions of using it.

But the varied response is similar for your transmission. Look up the towing procedures, and that will direct you to the safest route- per manufacturer.

[elhigh]

Coasting in neutral shouldn't hurt the tranny unless you turn the engine off. I coast with my tranny in neutral all the time, no worries.

[UltArc]

How to Tow an Automatic Transmission Toyota Camry | eHow.com

Coasting in neutral may be okay, engine on, but from this write up, I would be careful. For shorter periods, and the transmission normally running, I doubt itnwouldoverheat. But I'm also not a mechanic lol

[mcrews]

Originally Posted by UltArc

Engine on coasting, like everyone else said, really matters on the car and conditions of using it.

But the varied response is similar for your transmission. Look up the towing procedures, and that will direct you to the safest route- per manufacturer.

Help me.........do you tow with 'engine on'?????????

Does this thread talk about driving w/ 'engine off'?????????

Then PLEASE EXPLAIN the relevance.

THis pops up every time some asks about ENGINE ON COASTING IN NEUTRAL

There is NO CONECTION between the two.

[mcrews]

Originally Posted by UltArc

How to Tow an Automatic Transmission Toyota Camry | eHow.com

Coasting in neutral may be okay, engine on, but from this write up, I would be careful. For shorter periods, and the transmission normally running, I doubt itnwouldoverheat. But I'm also not a mechanic lol

Please explain why information on ENGINE OFF towing is 'causing you to 'be careful' when discussing engine ON

[mcrews]

FACT:
ran a 1997 Avalon w/ same engine and tranny for 210,000 miles. AND engine on coast in nuetral ALOT. Never had a problem.

Infiniti Q45 274,000 same.

[riva2model64]

Thanks for the knowledge everyone!

It seems as if coasting in neutral on a modern automatic is ok as long as the engine is on (mccrews personal experience attests to this). And coasting with the drive wheels moving with the engine off is not ok.

According to this article (blog?) from popular mechanics : Coasting in Neutral or Gear to Save Gas - Coasting and Fuel Economy - Popular Mechanics

coasting in neutral on an auto doesn't save gas. To be fair, this article is probably not a scientific quality, peer-reviewed study, and the writer seems to be a bit biased, but the logic seems to make sense. The argument of the writer seems to be that when a modern car coasts, the fuel injectors are off, so you are only experience engine resistance. When you shift into neutral, the fuel injectors turn back on to keep the engine in idle.

Interesting argument, but the issue with the article is that the 1 gph figure seems a tad high and the writer also didn't release the testing data.

With that in mind, I have another question

If you're parked in your driveway, and you want to move your car 10ft, is it ok to simply put the parking brake off, switch in in neutral and push it out of the way? Or is it better to to move it the normal way (turning it on and and reversing out)?

[MetroMPG]

Moving the car 10 feet is fine. But, again, realize you will not have power steering or power brakes (if the car has been off for some time) should you need them.

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And the problem with that Popular Mechanics article is that it tries to come up with a hard and fast "rule" on the topic. But the subject is more nuanced than that. Sometimes coasting in gear is better, sometimes coasting in neutral is more efficient. It's further complicated by differences between vehicles. There are lots of threads on the subject - try the search box top left of the page.

[UltArc]

Originally Posted by mcrews

Please explain why information on ENGINE OFF towing is 'causing you to 'be careful' when discussing engine ON

I was thinking key in the on position, not thinking about the engine being on. My mistake, this thread is lasting longer than my memory of first reading through.