Re: 2023 Crosstrek Auto shutoff

UFO <[email protected]> wrote:

> Thanks 2 all that commented. Great info.
> 
> I read the other day that the savings in gas is like 2.8 gal / yr and there 
> is a seperate battery being used to restart the eng and its like a $300 
> added repair expense when it fails.

https://www.varta-automotive.com/knowledge/articles/article-details/special-start-stop-batteries

As for fuel savings, Subaru claims auto-start-stop saves 3% to %10.  How
much you save depends on the grade (octane) of gas you buy.

https://www.edmunds.com/car-reviews/features/do-stop-start-systems-really-save-fuel.html
See the "How much can you save?" section.

All this auto-start-stop has most effect for urban dwellers having to
stop at almost every intersection in the city.  For rural dwellers,
their stops are far apart as they mostly drive on lanes and highways.
If you're out in the boonies, auto-start-stop won't save you anything.
If you commute in the city, especially downtown, yeah, you get to save.

As the Edmund article points out, savings depends on how much of an
electrical load you put on the batteries while stopped.  If the A/C is
running, you're pushing the stereo to max volume with max bass (you
know, those buzzing, rattling cars you hear at the stops), headlights
on, wipers wiping, and so on, then you have a higher electrical load,
including when stopped.  The higher the load, the shorter the off-cycle.

If you keep restarting while stopping, like creeping up behind another
car that crept forward, you keep cycling through start-stop cycles, and
that reduces gas efficiency.  You don't let the car stay stopped for
very long, so you effectively wipe out the savings.  Even tugging on the
steering wheel while stopped will restart the car.

While the savings may not be much to you, especially if you're not a
city dweller, car makers have to look at gas savings over ALL the cars
they sell.  Maybe you save 5 gallons per 20K miles, but then multiply
that by the over 600K+ cars Subaru sold per year, and add in the sales
volume for all other auto makers.  They're trying to put less pollutants
into the air.  

https://en.wikipedia.org/wiki/Start-stop_system
"In the United States, according to the Department of Energy, idling
wastes more than 6 billion U.S. gallons of fuel per year."

But the biggest reason auto makers add auto-stop is regulation (i.e.,
gov't overreach).  Law forbids car makers to exceed certain CO2 output
on average across their entire fleet.  The EPA offers gas mileage rating
incentives to car makers who configure auto-stop to On when the car
starts.  EPA deliberately tests in a manner that will lower the average
MPG for a vehicle whose auto-stop feature does not reset (to On) when
the car is started.

https://tflcar.com/2019/02/auto-stop-start-ask-tfl/
https://associationessentielles.fr/understanding-auto-start-stop-law-what-you-need-to-know/
https://blog.bestride.com/news/technology/auto-start-stop/

The gov't knows what is best for you whether you like it or not.  Car
makers have to bend to regulatory compliance.  Doesn't matter that the
hardened starter and AGM battery will last 3 times longer, because they
cost twice as much.  Those gas savings get eaten by higher maintenance
costs.  Because of all the stopping which lets the oil drain from the
engine, and despite accumulators, you have to change your engine oil
more often.  Not as bad when cold starting your engine where the oil has
drained since the engine and oil are at operating temperature during
auto-stops.  Electric water pumps are used to keep the engine cooled
during auto-stops, but now you have an electric pump to replace instead
of a much cheaper fan belt.  Luckily the transmission goes into neutral
during auto-stop.  The gov't wants to lower emissions.  They don't care
about increasing your cost of ownership.  There is also the issue that
when stopped, sometimes the auto-stop system doesn't start the car when
it is supposed to, or not start at all.  What if all wheels are locked
with heavy braking which activates the auto-stop, that could be when
sliding on ice or skidding around a turn when you really don't want to
lose power when needed immediately.  Some cars with auto-stop have
electric compressors for A/C, but some don't, so you get to cook in hot
summer in stop-and-go city traffic.

You can disable auto-start-stop, but likely it resets when you turn off
the car, so the next time you use the car it is enabled again.  You'd
have to get in the habit of starting your car, and hitting the disable
switch each time.  If the engage button is on the steering wheel, it is
a very minimal effort to tap it after starting the car.  If you forget,
you'll remember at your first auto-stop.  

Some other tricks I've heard are: a little less pressure on the brake
pedal when stopping, or really hard pressure after stopped, so the
stop-start indicator turns orange (off); setting the defroster to always
be on to increase the electrical load while stopped; an autostop
eliminator to reset on start what it was previously configured
(https://www.autostopeliminator.com/collections/subaru/products/2020-subaru-crosstrek-autostop-eliminator,
watch https://www.youtube.com/watch?v=nNykY8NdWng), but you're paying a
$100 to eliminate a nuisance that would be easy to ignore; putting the
car into Sport mode; making a rolling stop at a stop sign like everyone
else does; get an OBD2 dongle, plug it in, and see if you can reprogram
the ECU settings; don't use Drive, and instead select a driving gear
(turn your automatic into a manual); and probably some other trick to up
electrical load or keep auto-stop from triggering.