Any advantage to going to neutral and coasting

i've never used neutral, but it's pretty flat around here. you must be in mountain country. i'm sure you'll get a wide enough variety of resonses to completely confuse you.

 

>> I know one advantage is that when the ev battery on the PIP is depleted and you get up to 42 mph in ev mode the ICE comes on so if you have a stretch where it would accelerate past that the ICE wouldn't come on.<<
A good way to damage the transaxle. Neutral doesn't actually disengage anything. What you've described could drive the MG1 beyond its design speeds (though I guess that's more like 62 mph on the plug-in).

 

Sure it's illegal, it's also dangerous and pointless. Though I'm pretty sure it won't harm the CVT in any way (which is not really a CVT anyway, it would be better called an "Electric/ICE power splitter), it will surely inflict wear on your brakes (the disc ones, not the regenerative one). In D mode, with a full charge, the ICE will kick in when you let go of the gas pedal in a downhill, or whenever you use the brake pedal, but it won't use any gas. The only thing it will do is pumping air in order to dissipate energy with no harm done, as it will be properly lubricated during the whole process. On the other hand, doing the same thing in neutral would unduly tax the disk brakes (with resulting wear), possibly to the point of causing them to fade out. Both the law and common sense dictate the same thing: Don't ever drive ANY vehicle in neutral ! (regardless of power system or transmission).

 

This is just a general "Prius" philosophy I personally apply.

But I'm going to let the machine...be the machine it is designed to be.

By that I mean, when I owned my Honda Fit? If I was in a long line in a drive through? I turned off my engine. With my Prius? It handles that itself....I don't bother powering down....

Any advantage to coasting in neutral?

I don't know, and I don't care. The vehicle was designed to be driven in Drive. Any momentary or slight perceived advantage is almost immediately negated by risk to the entire HSD system.

Illegal.
Potential Harm to The System
Questionable if not negligible advantage at all

I'm voting No.

 

Wow, yeah, that's the one case you REALLY should not use neutral. That is how you damage MG1 by over-reving it. The ICE comes on in that case to protect it. Other times (without going down a hill) it is still pointless to use neutral, but at least it won't cause damage!

 

The only really stupid question is the one that you don't ask. At least....that's what I used to tell folks when I rode a podium.
About the only way that I can think of to answer this question without incurring the wrath of the mods is to point out that it is indeed illegal to place your car in Neutral while driving down the road hill or no hill. There are 50 states, and so one or two of them (probably flat ones) might not have gotten around to making this activity illegal.
That's NOT the same as an endorsement!
There's a pretty good reason for this, and it doesn't have anything to do with the fact that we pay legislators by the pound for the paper that they use when they make up new and interesting ways to control your life.....and (spoiler alert!) no. It's not because the folks in your state capitol are buzz-kills that want more of your fuel tax dollars. It's not a mattress tag law.

Really.
Juuuuuuuuust leave the car in "D".

 

Yup, PiP can go 62 mph with ICE off. You can take advantage of it but don't let it go above 65 mph with ICE off in neutral.

In D gear, I have seen ICE off at 65 mph in EV mode but that was downhill. ICE started at 66 mph to protect MG1 from overspeeding.

 

Do you really believe that? Because I'll admit I've had some REALLY stupid questions that I have NOT asked over the years. And usually later? I sit back and go "Glad I kept my mouth shut about THAT."

 

When going downhill with a full battery and the ICE switches on it runs until it reaches the proper operating temperature. To avoid follow strategy outlined near the end of this thread.

Living on top of a hill | PriusChat

 

There are very few absolutes in the universe and even stupidity has its bounds, Einstein's famous quote notwithstanding.
So yes Virginia, there are stupid questions in the world.
Usually though, people who have enough lumens of noodle power to ask a question are at least bright enough to ASK the question.
The folks who scowl at the world and mutter "those laws are for folks who don't know what they're doing! "...


THOSE are the ones that you have to watch out for!

 

I don't know. Sometimes humanities stupidity seems pretty boundless to me. Or at least it's an envelope we seem to love to push.

Seems to me it doesn't take a lot of intelligence to ask a question. It takes more intelligence to know whether a question is worth asking.

I'm thinking along the lines of "Is there gas in that tank?" being asked by the guy looking in the tank holding a lighted match.

There are just some cliche's that get used often that I don't have too much respect for, because I don't think they survive under the scrutiny of reality.

There are no stupid questions....is one of them.


The other is " That which doesn't kill you, only makes you stronger."

No, I've witnessed plenty of things that don't kill you but leave you weaker. Sometimes just making you weaker and weaker until the thing that does kill you comes along.

I suppose my "dumb" question here was right at the beginning...."Do you REALLY believe that?"

 

I assume you ate talking about Wayne. He does that so he doesn't have to teach them a proper glide at the time.
Another downside is that you won't get regen if you need to brake while in neutral.

 

Wayne Gerdes has students initially use neutral to get an immediate feel of a true glide. With practice, they should graduate to doing this with just foot control on the gas pedal, without actually shifting to neutral. But for students who have not already being doing this, his in-car tutorials are not long enough to get there.

 

Well, here is a situation where N seemed to called for. I did this a lot on my 2005 Prius. Whether the PiP in hybrid mode behaves the same way, I am not certain. I think I did check and it does not.

I live at 9500 ft and roads here go between 8000 and 12000. For the '05, climbing a hill would deplete the battery and then, on a subsequent long downhill, the control system (when in D, but not in B) feels like it needs to run the ICE to generate power. Putting it in B suppresses that, but it can be too slow. So I would go in N for a bit until speed was up to, say, 73 or so, then B to get back down to 65. Repeat. The battery would then recharge to good levels, with no need for gas use.

Now, I read on these forums that using N above about 65 is not a good thing for the motor. [[Note that there is no issue with braking. There is a safety issue I know, but so far so good.]] Yet I detected no problems because of my N behavior and the Prius 05 hit 100000 miles. Just sold it as I have the 2013 PiP. Of course, this does not mean I was not doing any damage.... but nothing ever arose.

So I guess the question is: Does anyone know with certainty whether the PiP when in hybrid mode behaves the same way?