Those cars that turn off stupid questions. Just curious

It looks like the future will be the cars that shutoff at stoplights then restart.  Stupid questions are as follows:

1. Is this hard on engines or starters? Other parts?

2. Are starters wearing out sooner?  Batteries? Compression issues?

3. Are starters still $35 at Trak Auto with a lifetime warranty?  

4. If I drive 150,000 miles in six years am I saving $2-$3,000 over this period?  If not, what can I expect?

While I'm at it; how much does a Tesla guy pay the charging meter when sitting in a grocery store hookup?  $3? $30?

1) Generally speaking, auto stop/start isn't enabled until the engine reaches some threshold temperature, so it's not particularly hard on the engine.

2) Generally speaking, the manufacturers know that the starter is going to get used more heavily, so they engineer it to handle the expected additional use.  I expect they probably don't enable it until the battery has reached a certain charge state, so it's not any harder on them either.  Not sure how compression would be affected.

3) I doubt it

4) The improvement in fuel milage is going to depend on your mix of driving, obviously it's not going to do much if you're mostly driving on the freeway.  It's not a huge amount of savings even in the most optimistic cases

EV charging costs vary a lot.  Different states regulate it in different ways, and the rate you pay also varies with which charging network you use.  Some of the early adopter Tesla cars got free charging for some time (perhaps lifetime?).  It's generally a lot less than buying the gasoline for the same distance though.

Auto stop/start has been around for over a decade, and there's no major objective downside to it.  Subjectively I find it really annoying (it trips the alert in my brain thinking that the car has stalled), so I generally turn it off in my Audi.

The general answer is that thanks to Direct Injection, it isn't really any harder on modern engines compared to older style engine designs.

1) Not really.

2) Batteries are consumables and modern cars are generally harder and more sensitive to bad/weak batteries.  This has nothing to do with autostart solutions.

3) They could be, depends on how many different variations there are and how often they need to be replaced

4) Not sure, too many variables to use a blanket statement.  Comparing something like my Focus RS to a base model Focus would be quite different.  Let alone various manufacturers and models.

Depends on the company.

I thought I remember reading somewhere that the restart after the auto-stop was handled by the alternator. 

Start-stop engines do have heavier-duty starters, they also have special engine bearings to reduce startup wear - usually this can be seen as a reddish coating.

The auto-start in our 2020 Odyssey certainly uses the starter.  I can't get over the mental freak-out of having the engine off while I'm waiting to make a left turn (or whatever) and that extra half-second is time I want to use to move, not whirr, so I try to turn the system off every time I start the car.

If the Sienna Hybrid had been available when we bought the Odyssey, we probably would have gone for that instead, thus making the whole business irrelevant.

I read somewhere that auto stop/start was more to reduce emissions than to increase fuel economy.  May have read this in my f80 M3 owner's manual

I had never driven an "auto shutoff" vehicle until this week - I currently have a Cadillac XT5 rental and I'm not used to it yet after three days. I find it annoying. But I do like the idea of buying less gasoline.  Edit: or reduced emissions
 

Like the OP, I used to wonder about starter longevity but figured (as suggested above) that's been contemplated by the auto engineers. So no big deal. 
 

A thought crossed my mind though... what happens if I stop and the car shuts off and I see somebody out the corner of my eye about to t-bone me. I want to mash the gas and move. But the car needs a moment to restart. Other than that 1:1,000,000 scenario I don't really see a downside.

wae said:

I thought I remember reading somewhere that the restart after the auto-stop was handled by the alternator. 

Depends on the car.  IIRC, GM did this more than anyone else.  That being said, the "mild hybrid" design is basically an motor-generator that can start the motor and provide a few HP boost in certain maneuvers- a pretty inexpensive way to get back some of the stopping energy.  

M2Pilot said:

I read somewhere that auto stop/start was more to reduce emissions than to increase fuel economy.  May have read this in my f80 M3 owner's manual

 

That, I very much doubt.  The FE improvement is really obvious.  The emissions takes some serious development to keep the exact same.  This is one of the big things I've been working on for the sunset of my career.  

OHSCrifle said:

I had never driven an "auto shutoff" vehicle until this week - I currently have a Cadillac XT5 rental and I'm not used to it yet after three days. I find it annoying. But I do like the idea of buying less gasoline.  Edit: or reduced emissions
 

Like the OP, I used to wonder about starter longevity but figured (as suggested above) that's been contemplated by the auto engineers. So no big deal. 
 

A thought crossed my mind though... what happens if I stop and the car shuts off and I see somebody out the corner of my eye about to t-bone me. I want to mash the gas and move. But the car needs a moment to restart. Other than that 1:1,000,000 scenario I don't really see a downside.

That last part is very much in the mind of developers.  There have been a number of lawsuits over lack of something happening, so keeping that not actually happening is a very big deal- so the engine will start as you lift off the brake pedal- just before you mash the gas.  Which is to say, don't left foot brake with start-stop.

And for some, a slight lift off the brake will start the engine and it won't re-stop until you really push the brake down hard.

I've driven a few cars that had the auto-stop/start feature.  I found it really disconcerting and sought out the disable button immediately.

VW was really thoughtful and made it a single simple button right beside the shifter.  So it was a feature and I'm sure as a brand they get some governmental brownie points for saving those three thimblefuls of gas over the life of the car, but it can be defeated instantly and easily by those who find it obnoxious.  (In a black car in Hawaii and want to keep the AC running in traffic for instance)

KyAllroad said:

  In a black car in Hawaii and want to keep the AC running in traffic for instance

My Focus 4 has an easy to reach override button but I "generally" leave it active. You need to be pressing the brake pedal fairly hard to activate it so on most level roads light pressure will hold me stationary with the engine running.

A/S is inactive when the engine is cold, the battery is a bit flat, the interior temperature is more than 2 degrees different to what you've asked for, a/c is on max or the steering wheel is more than about 30 degrees off centre.

In reply to KyAllroad :

In at least some cases, auto stop will not activate if temp is over a certain value so that ac continues to run.  In the one car I've owned with the feature, I didn't mind it at all. I actually sort of liked it. Pressing the gas pedal or any steering input would start the car & it didn't shut off on hot days with ac running. The tiny delay that restarting caused acted as a reminder to look left & right 1 more time before entering an intersection.

We're currently in the phase where manufacturers are still figuring out how to implement these systems well, though we've finally gotten to the point where some are starting to figure it out. I've experienced older bmw systems and they were awful. But I've also driven a new f150 with it and it's not bad at all. The owner is somebody I thought would hate it but he said he got used to it pretty quickly.

I also assumed the effect would be minimal, but iirc last time I said that somebody replied that there was some testing done that showed like 10% improvement in pure local driving which certainly isn't insignificant.

At least on the newer well implemented systems the conditions under which the system operates are pretty tightly controlled. I've always kept it off in my cayman (turns out sport mode which I always drive in disables it anyway), but lately I tried turning it back on just to see what it's like. But I haven't managed to get it to actually engage, I assume the approaching eight year old original battery is a little bit too weak or something.

alfadriver said:

And for some, a slight lift off the brake will start the engine and it won't re-stop until you really push the brake down hard.

My wife's car has it (VW GTI) and the delay to restart the car is longer than it takes me to lift off of the brake, press the gas and get irritated I'm not moving. For normal people, it's probably way less noticeable.

The engine will also restart if you turn the steering wheel.

I read the title to mean "cars which deter those questions which are stupid."

I wasn't sure what might have been meant by that.

I've been driving hybrids for so long now, I panic when the engine doesn't auto stop.

red_stapler said:

I've been driving hybrids for so long now, I panic when the engine doesn't auto stop.

Yes. As hybridization spreads, this becomes even less of an issue. Mild hybrids like Chrysler's E Torque use a heavier alternator to control this. More traditional hybrids like Toyota or Ford products may not even have a starter.

In reply to Brett_Murphy (Agent of Chaos) :

What year GTI?  Ours is a 2018, 6 speed, and it doesn't have it.  My M2 has it, and it seems like an oversight on the VW. 

In the M2, you have to be in neutral, foot off the clutch.  I now play a little game where I time everything and see if I can still "beat" the cars in the other lane.  Not in a drag race, but in terms of getting going.  Dumb fun.

alfadriver said:

M2Pilot said:

I read somewhere that auto stop/start was more to reduce emissions than to increase fuel economy.  May have read this in my f80 M3 owner's manual

 

That, I very much doubt.  The FE improvement is really obvious.  The emissions takes some serious development to keep the exact same.  This is one of the big things I've been working on for the sunset of my career.  

I have read that the big win for stop/start tech is in the milage test used for the CAFE rating (which is the old one that is no longer used for the window sticker numbers).  Adding something like half a mpg there is worth a lot of money to the manufacturers, even if it's not something that you'd notice as an owner.

M2Pilot said:

In at least some cases, auto stop will not activate if temp is over a certain value so that ac continues to run.  In the one car I've owned with the feature, I didn't mind it at all. I actually sort of liked it. Pressing the gas pedal or any steering input would start the car & it didn't shut off on hot days with ac running. The tiny delay that restarting caused acted as a reminder to look left & right 1 more time before entering an intersection.

If the car has engine-driven AC then yeah, it's not going to shut it off when it needs the AC compressor.  Electric AC compressors have become a lot more common though, even on non-hybrids.

Some of the start-stop systems track what cylinder the engine stopped at, and if it hasn't had too much time pass since the engine shut down, restart the engine by activating the spark plug on the cylinder that was ready to fire.

I know Honda uses a "starternator" for their scooters with auto start-stop.  Is that what the car manufacturers use, too?  If so, I'd kind of assume they are heavy duty enough that we might get lucky and they'll be more durable.

MadScientistMatt said:

Some of the start-stop systems track what cylinder the engine stopped at, and if it hasn't had too much time pass since the engine shut down, restart the engine by activating the spark plug on the cylinder that was ready to fire.

For real!?  Sometimes it's just freaking amazing to be living in the future!