Any benefit to shifting the auto from D to N at a stop?

[voodoo22]

When you come to a light and the situation or length of light doesn't allow you to turn off the engine responsibly, do you think it serves any purpose to shift the car into N?

When I do this at a stop, I find the rpms rev up a little, but the car seems to loosen up as it's not fighting the brakes, but I don't know if it's worth it, good or bad.

What do you think?

[Astroman]

Bailout, where are you?

[sherryberry]

I was told to not do that cuz it can mess up the transmission *shrugs*

[BailOut]

lol Astroman,

I would need an AT Yaris I could test while using an SGII as there have been a lot of tricks created over the years to make ATs more efficient at a stop with the brakes applied, but I have no idea if the Yaris deploys any of these.

If anyone with an AT in the Reno or Sacramento areas would be up for this just let me know.

[Astroman]

I do feel more engine vibration (almost like it's trying to give more gas to keep the engine from stalling) when I and stopped with the brakes and in gear, and the vibration is much more intense with the A/C on. (Only been using it because there is a big forest fire nearby and the air is dirty. Gotta protect those lungs.) When I put it in neutral I can't even feel the car run. Dunno if it is any better/worse though.

[caveatipse]

It is not good to shut off your engine at lights, because you would be stopping and starting it all the time and it would wear on the engine. Second, the transmission is designed for the car to come to a stop in D. The transmission has slipping plates and gears in grease or oil that are designed to give way precisely so that the car is not fighting against the brakes. Also, idling is harde ron an engine that being under load, or so I have read.

[swng]

Unless the stop is going to be too long, I would rather step on the brake and leave the transmission in gear so that when there is a sudden demand for power, I get it immediately. One never knows. Auto trans are designed to withstand this anyway. If the stop is going to be too long and I do shift to neutral/parking, I will leave my hand on the shift knob as far as the situation allows so that when I can move again, I will always remember to shift back to D first before I step on the throttle.

[BailOut]

Originally Posted by caveatipse

It is not good to shut off your engine at lights, because you would be stopping and starting it all the time and it would wear on the engine.

Wrong! See http://www.yarisworld.com/forums/showthread.php?t=5979

[caveatipse]

Originally Posted by BailOut

Wrong! See http://www.yarisworld.com/forums/showthread.php?t=5979

Sorry I just do not believe it. Cranking the engine up and shutting it off again and again all day long wears on the engine and wears out the starter.

[BailOut]

Just because you don't believe it doesn't mean it isn't so. Please think twice and ensure you are knowledgeable on the subject at hand before the next time you give advice.

[alhope34]

I never change to N at a light. Like others have said, it is not necessary to do so.

And turning off the engine at a light is just silly... It is really annoying to be stuck behind someone standing there trying to crank their car over and get it in gear properly. I don't know what the laws are like in other places, but in Ontario that is considered "standing" which on just about all main roads is illegal, ESPECIALLY in the left lanes. I have seen cops pull over people who turn off their engines at red lights and I have heard that the tickets can be more than $100 depending on how annoyed the cop is.

[caveatipse]

Originally Posted by BailOut

Just because you don't believe it doesn't mean it isn't so. Please think twice and ensure you are knowledgeable on the subject at hand before the next time you give advice.

And just because you believe it does not make it so. Why don't we both do some more scientific research and then share our findings? I certainly could be wrong, but I have read that before. I will check again.

[BailOut]

Originally Posted by caveatipse

And just because you believe it does not make it so. Why don't we both do some more scientific research and then share our findings? I certainly could be wrong, but I have read that before. I will check again.

The day you top my 52.5 MPG record we will talk.

[caveatipse]

Originally Posted by BailOut

The day you top my 52.5 MPG record we will talk.

But I am not talking about gas mileage. I would imagine that, yes, gas mileage is better if you turn your engine off every time you stop. I was actually talking about wear and tear on the engine and the starter. I contend that wear and tear is greater if you are constantly turning your engine off then back on.

[xpeteyjtx]

Yea, wear and tear is greater. But... the wear and tear might be minuscule since the engine is already warm and well lubed (in comparison to a cold start). If you want the engine to last 150,000 miles, my guess is that shutting it off/turning it on at a red light won't make a difference. But by 250,000 miles, it may start to consume some oil. Obviously, I'm making these numbers up, but you get what I'm saying.

If you do shut it off/turn it on, the starter is being worked more. It would be interesting if Toyota released cycle ratings on their starters. That could give us an idea of how long they would last.

That being said, I personally don't shut the engine off. I don't idle too long at red lights since they seem to change quickly, so it's not really worth it to me.

If someone was up for it, they could do a little experiment with UOAs (used oil analysis). They could do a few samples with the shutting the engine off technique and then do a few with leaving it on. Obviously, constants such as oil brand/weight and change interval must be kept constant, along with driving style. Also, it would be best if the engine had more than 30,000 miles, so that the numbers shown on the UOAs are normalized

[voodoo22]

Thanks for the thoughts. Hopefully someone with a scanguage on an auto can test this one day.

I personally don't believe shifting to N at a stop can make much of a difference, because Toyota knows 99.9% of people won't do this and I'm sure they taken measures appropriate to that knowledge. I just don't want to do it, if it's causing more problems than good.

I never coast in N, when I am coasting in heavy traffic or approaching a red light, I will shift from D to 3 if I'm going under 80 km/h to try and save the brakes and improve the chances of benefitting from DFCO.

I also shut off the car when I'm at a long light and I do pay attention to the other lights so I don't inconvenience all the IMPORTANT people who have to tailgate and don't have time to use signals while they speed up to the next red light or slow spot of traffic

So far I've been doing very well on gas, but the cold weather is coming and I can feel the FE slipping away!!

[black2yaris]

coasting in N in an auto tranny will wear the bearing seals out as the a/t is NOT pumping fluid around the tranny in N (even if the engine is running) & the rear bearing seal heats up due to no lube & fails in short order ..(Yeah you might do this now with no sign of a problem, but you are ruining yer tranny just to save a few cents) that's why tow trucks haul cars with RWD tail up on the hook & FWD with the fronts up on the hook.... This is Wise to remember this when you break down ! That a Towtruck driver could give a F**k if he burns yer car's tranny up

[black2yaris]

As for shifting into N from Drive at a red light the savings are Very Low & the damage (wear & tear ) to the linkage & valve body on the the tranny , is far more costly in the long run than the few cents you save shifting into N . Just think how many Extra cycles that you are adding to the linkage & valve body over the life of yer car , by doing this ! Those Car Parts only have a set amount of cycles in them before they fail (like in any car part the moves ).... Think Starter also here, to those who kill the engine at a red light ! Now I'm all in for F E here but at the cost of replacing linkage,trannys , starters , switches and other parts , all the while by trying to save a few cents on a tank of gas is just plan stupid .