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Is the engine start/stop a gimmick car manufactures use to inflate mpg?
- Thread starter JealousKenny
- Start date
I think I had this on a Jetta I rented recently for a work trip. I didn't mind it, seemed responsive enough and I am all for anything that reduces emissions
Going to get an EV and hopefully never look back though
Going to get an EV and hopefully never look back though
My car does this, I don't mind it. When it's hot it's a little annoying because the AC drastically reduces so if it's a long stop you feel it slightly.
....but it does improve MPG. Because you aren't wasting fuel when stopped.
Start stop systems absolutely do make a positive difference in terms of fuel consumption, and cars equipped with these systems are outfitted with beefier starter motors to handle the additional use. I'll say the best system I used was on a rental '19 RAV4, where start stop only engaged if you really buried your foot in the brake pedal when at a stop. A really elegant way to allow the driver to opt in and out of the system depending on circumstance if you ask me.
It's such a small difference in mpg though, you're saving pennies in fuel.
Was driving the same car yesterday. :D
Haven't driven it in the summer.
Girlfriend has a 2011 Mercedes.
We haven't noticed anything.
As someone who works in the industry, it's advertised as an MPG saving feature but in reality it's more about cutting down emissions. The fuel you are actually saving is so minimal that you won't really notice a difference whether you have it on or off. When these systems were introduced, the engines and starters were redesigned to be able to handle the extra wear and tear that it causes. Personally, I hate the feel of it so I disable it any time I'm in a car with it which seems to come standard on most cars now.
I think the belief is that since oil isn't circulating when the engine is off, parts end up not having enough lubrication. But that's not true. There's enough oil still stuck to the components that the engine will be fine. Or it could be about the starter/battery getting extra wear but those degrade more due to time than due to usage cycles, I believe.
I get that it's annoying, but it does reduce pollution.
The Start/Stop on/off button is located in the center console. Car needs to be in park and press the button. It's true you have to do it every time you start the car. But it's not really a "process". It's not like it's buried in the menu's of the multimedia system.
OP
OP
I specifically looked up the instructions for Jeep Compass (2016-2019). But maybe you are driving the first gen Compass. I can't seem to find the button anywhere on the dash or center console of the first gen Compass, so I can understand your frustration, if it's a pain in the ass to turn it off with that model year.
It drives me nuts when I rent cars too OP. I usually find a way to turn it off when I'm driving because I hate that sputter feeling... some cars it's more noticeable. That and the steering assist on cars, I find to be tough - if I owned the car, I think I would get used to it, but I rent cars 10-12x a year and it's just something I feel like I'm battling with the car about.
Neat - but I thought it was either frowned up, or illegal to do this since if you get rear ended when in neutral you're more likely to hit a car in front of you or go into cross traffic?
With a manual transmission, putting it in neutral when stopped at a light is what everyone does. Leaving it in gear would increase hitting the car in front of you or going into traffic if your foot slips off the clutch pedal.
no, my car barely uses
2019 forester sport and you need to press the break all the way for it to activate. I still average 31.8mpg in the northwest burbs in my vehicle with the start stop.
It also doesn't save much honestly
I have almost 2 hours of it off and it says i saved maybe a gallon.
2019 forester sport and you need to press the break all the way for it to activate. I still average 31.8mpg in the northwest burbs in my vehicle with the start stop.
It also doesn't save much honestly
I have almost 2 hours of it off and it says i saved maybe a gallon.
Google that guys name and you'll probably see why you shouldn't listen to anything he says.
Jesus, carmakers need to just adopt EV. All these complicated features to reduce fuel consumption and air emission.
Yeah, in an electric vehicle, there's no need to worry about ignition period. And in a good hybrid setup, it shouldn't need the gas engine to pull away from a stop, so there isn't any delay to worry about.
They're good for hundreds of thousands of cycles
Scotty doesn't know
If you are in first gear and you remove your foot of the clutch - because you get hit from behind for instance - you will move forward.
Yeah.
I watched a video on this where they measured fuel consumption and starting usage was equivalent to 7 seconds of idling.
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Given that even a short red light is about 30 seconds long, that's quite the difference in idling consumption.
My aunt has a Jeep and it's absolutely annoying. Hearing the noise starting/stopping stress me way more than it should.
I'm pretty sure I've driven every single car mentioned in this thread and it's been annoying on every single one. Great that others don't notice it, but I absolutely hate it. I immediately turn it off on every car I can.
I'm thinking of every friend, co-worker, and fmaily member I have with a car with the feature, and they all turn it off when they can. I'm all for better gas mileage, but this is just really annoying.
EDIT: A tesla at a red light has never been annoying. I'll admit that.
I'm thinking of every friend, co-worker, and fmaily member I have with a car with the feature, and they all turn it off when they can. I'm all for better gas mileage, but this is just really annoying.
EDIT: A tesla at a red light has never been annoying. I'll admit that.
I think it comes down to whether you find the sensation annoying. I had a Cadillac XT4 rental where it was noticeable, but generally unobtrusive, but I've been in other cars where it sends a shudder through the chassis, which is less than desirable.
My cousin has a 2019 RAV4. I've only been in the passenger seat of it - but there's a button she can use on the steering wheel to disable. First time I was with her, I said I hated that feature. She was like ,"OMG so do I!" I told her about the button and I'm pretty sure she disables it each time she drives.
Can't comment on a 235i, I admit. I've only driven an M2, but it was a manual so no auto start/stop.
The manuals have it :) Mine was a 6spd. I always found the transition pretty smooth but I can see how people might not love it. With that said, what I've noticed in the RAV4 hybrid is it engages the electric motor before it switches to gas which seemingly smooths over the transition. I could be making that up, it's my gf's car, but that's how it has felt to me when I'm in it.
I reckon this is the case, yah. I've driven Hondas where it was definitely much more jarring than the bimmer or rav4.
is it as annoying as, oh, adding a bunch of unnecessary pollution to the atmosphere?
we all make sacrifices 🙄
my car doesn't have it, but if I'm at a longish light, yeah I turn it off.
we all make sacrifices 🙄
my car doesn't have it, but if I'm at a longish light, yeah I turn it off.
I can't see it not effecting the starter and honestly it hasn't really been a feature long enough to know if it will or not. I don't have it in my Jeep but it seems like it would be annoying though and honestly kind of dangerous if you need to quickly move to stop someone from rear ending you.
My 2017 Ford Fusion has the feature but it very rarely is used. I wonder what's the algorithm that decides whether or not for it to kick in.
As an industrial air quality engineer, I think it's mostly a gimmick but I haven't actually run the numbers. Typically for combustion sources, emissions are the worst during startup and shutdown events so it probably evens out with a potential of emitting worse things than you would during idle due to increased amounts of incomplete combustion. Ultimately if it uses less gas, even while emitting worse things, the MPG will increase, which is a selling point.
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I have been leasing Minis for awhile and have turned it off immediately in the last two cars I've had. It's quite obnoxious frankly.. but the mpg I get is pretty shit in my Cooper so if it's proven to actually make a difference I may consider turning it back on.
Wait... how does the start/stop work with a stick? It definitely didn't do it by "default" in the M2, as I would have noticed.
Only when pulled in neutral? Many stops I keep clutch engaged and stay stopped on first - how does it kill it? I'm sincerely curious; never run into that.
You have to be in neutral and clutch pedal must be disengaged. The motor restarts as soon as you touch the clutch. If you keep the clutch in and the car in gear at rest, it'll never turn off. I believe that when in Sport mode it disables auto start/stop.
I can't speak for whether this is any different in the M2 vs. the M235i though.
I don't know, he's helped me repair my wife's car many times lol. I'll look him up though.