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Old 02-16-2020, 10:14 PM
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Why do new cars shutoff at intersections?


A few months ago I rented a car for a business trip.

It started shutting off at intersections. Then, it would start agin when I went "what the hell?" and took my foot off the brake.

Why? What's the reason?
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Old 02-16-2020, 10:16 PM
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To conserve gas, of course. When it's running, even just idling, it's burning gas.
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Old 02-16-2020, 10:40 PM
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Got it in one. Saving gas and not polluting the air are both good things in my book.
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Old 02-16-2020, 10:57 PM
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It's called a start-stop system.
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Old 02-16-2020, 11:11 PM
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There have been a number of threads on this topic before (here's one).

The gist is that it really does save a significant amount of gas during city driving.
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Old 02-16-2020, 11:33 PM
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modern cars with fuel injection and electronic ignition (and computerized fuel and timing controls) are far easier to start. Many now have a one tap push-button start rather than a push and hold to start. Thus, unlike the old carburetor system, they don't take a lot of time or extra gas to start, especially when the engine is still hot. Starting automatically when you take your foot off the brake (or wiggle the steering wheel) is fairly simple tech. So turning off when stopped is very fuel efficient. I should note that when the air conditioning or cabin heat warrants, the engine will start automatically once the heater/cooling has gone beyond optimum temperature.

Last edited by md2000; 02-16-2020 at 11:33 PM.
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Old 02-17-2020, 12:36 AM
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I think we're all stuck with the intuitive notion that starting an engine is, in some sense, a stressful and inefficient operation (for the engine, or battery) and it's best not to do it too much. md2000 notes that this was the case with older engines with carburetors.

I saw somewhere (years ago) that it was most efficient to stop and re-start the engine if one expects to idle for more that 90-or-so seconds, but if idling for less time than that, keeping the engine running wins out. Obviously, that isn't the case for modern engines.

Airplanes seem to have a much longer life than cars for some reason, and lots of little airplanes from the 1980's and even earlier are still flying. They all have carburetors. Newer airplanes, like cars, are fuel injected. But I suspect they all still keep the engine running at red lights.
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Old 02-17-2020, 12:48 AM
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I just got a new Subaru, and initially thought it would annoy me. But I'm giving it a chance, I discovered that it's pretty smart, there are certain configurations where it doesn't shut off - notably if you are signaling a turn when you're waiting for a gap in traffic. So in that situation there's no safety concern unless you're a dick who doesn't signal.
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Old 02-17-2020, 01:32 AM
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Our most recent vehicle, a 2017 Kia Sorrento, lacks this, but I work manual shutoffs and restarts at obvious delays like roadwork blockages - I don't bother killing the ignition at the five stoplights in this county. (I think there's that many.)

Electric vehicles of course don't burn juice while awaiting traffic signals, and neither do steam vehicles. Steamers would be ideal quiet, low-emission, no-burning-fuel-while-stopped vehicles for urban congestion. If Big Oil wants to keep selling the usual petrol to consumers, they'd better push development of modern steamers.

I foresee a future where existing internal combustion vehicles are grandfathered past the upcoming electric mandate but all ICEVs are chipped for external control that kills their engines at traffic stops. Governments will likely demand autonomous-run kits for older vehicles, too. Enjoy the ride.
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Old 02-17-2020, 04:09 AM
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I foresee a future where existing internal combustion vehicles are grandfathered past the upcoming electric mandate but all ICEVs are chipped for external control that kills their engines at traffic stops. Governments will likely demand autonomous-run kits for older vehicles, too. Enjoy the ride.
Come to Europe where it's already happening. Any car here built this century will probably have the stop/start feature. It was the inevitable response to the ever-tightening rules on exhaust emissions and increasing fuel costs/taxes. By 2040 or so (reducing) ICE-powered cars will be history.

The concern about wear and tear from the start/stop function is widespread, and in groups relating to my car, I have seen many requests from people who want to turn it off (It can be done). The other thing I see on those groups is that people whose cars are around five years old are reporting that it has stopped functioning (along with some other electric gadgets). This is because their batteries are beginning to fail. If the voltage drops below some preset point, the car progressively switches off un-needed features. Stop/start is the most power-hungry so it goes first, followed shortly by the heated windscreen (it may be vice versa).
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Old 02-17-2020, 04:41 AM
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I rented a Jetta about a month ago that did that. The odd thing was that the restart at intersections was quite different than when starting the car from a cold start. In the latter case, you pressed the button (it was keyless start) and you could hear the starter motor cranking and the engine starting in the normal way. But when stopped at a red light, say, the engine would just go quiet, and taking your foot off the brake or turning the steering wheel would suddenly cause it to come alive without any of the normal sounds of starting. It was as if the engine wasn't really off, but in some kind of "sleep" state. It was also a feature that you could optionally turn off if you didn't like it, and then it would idle normally when stopped. I left it on because I thought it was kind of cool, but it struck me as one of the many, many things that can go wrong on high-tech cars as they age.
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Old 02-17-2020, 07:01 AM
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Yeah, I rented a Volvo a few years ago right when this was getting implemented. Drove me nuts at first, and I kept restarting it until it dawned on me what was up.
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Old 02-17-2020, 07:09 AM
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Many now have a one tap push-button start rather than a push and hold to start.
Even before the push button starts they did that. I had one or two cars that were designed so that you'd turn the key like any other car, but you could let go right away and they would crank until started. I got so used to it, if I started a regular car, it wouldn't start on the first try because I'd let go of the key to early.

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Thus, unlike the old carburetor system, they don't take a lot of time or extra gas to start, especially when the engine is still hot.
They (or at least the car that I had that did the stop/start thing) have a high power starter, designed to start the car much quicker than a regular starter. Presumably it also has a longer life since it might have to start the car 50 times a day instead or 3 or 4 times.

Also, a trick I learned, and this is surely different for every car. If I wanted the engine running while at a stop, I could keep my foot on the brake and tap the gas pedal. That would get it started and it would stay running until the next time I stopped. Helpful if I wanted to get the AC kicked back on or if I'm waiting to pull onto a busy road and didn't want the half second lag before I could go.
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Old 02-17-2020, 11:18 AM
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I rented a Jetta about a month ago that did that. The odd thing was that the restart at intersections was quite different than when starting the car from a cold start. In the latter case, you pressed the button (it was keyless start) and you could hear the starter motor cranking and the engine starting in the normal way. But when stopped at a red light, say, the engine would just go quiet, and taking your foot off the brake or turning the steering wheel would suddenly cause it to come alive without any of the normal sounds of starting. It was as if the engine wasn't really off, but in some kind of "sleep" state. It was also a feature that you could optionally turn off if you didn't like it, and then it would idle normally when stopped. I left it on because I thought it was kind of cool, but it struck me as one of the many, many things that can go wrong on high-tech cars as they age.
One would think, but stop-start systems have been around for 10 years now and I havenít heard any reports that they require more repairs than other cars.
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Old 02-17-2020, 11:52 AM
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My 2010 Prius did this, and I never noticed a lag starting up again when it turned off the engine at an intersection.

Push button ignition is new, but after car thieves scooped out my ignition twice when I lived in Cambridge, I wired my car with a toggle switch and a button to start it. Worked fine.
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Old 02-17-2020, 12:29 PM
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My 2010 Prius did this, and I never noticed a lag starting up again when it turned off the engine at an intersection.
The Prius is a bit different, being a hybrid. It starts moving on battery power before the engine kicks in. On conventional cars with a start-stop system, the engine needs to start before the car can move.
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Old 02-17-2020, 12:38 PM
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.
. But when stopped at a red light, say, the engine would just go quiet, and taking your foot off the brake or turning the steering wheel would suddenly cause it to come alive without any of the normal sounds of starting. It was as if the engine wasn't really off, but in some kind of "sleep" state. .
As I understand, when the engine is temporarily stopped, the engine controller remembers exactly what angle the crankshaft is at. So the spark plugs and fuel injectors can start firing immediately, before the crankshaft even makes a full revolution. And of course the engine is already warmed up.

Last edited by scr4; 02-17-2020 at 12:40 PM.
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Old 02-17-2020, 02:08 PM
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My 2019 Cherokee has a button I can hit to override the start-stop system, but I have to hit the button every time I first start up . If I stop and go into a store or something and shut it off, I have to disable it again when I start driving again.
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Old 02-17-2020, 02:08 PM
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As I understand, when the engine is temporarily stopped, the engine controller remembers exactly what angle the crankshaft is at. So the spark plugs and fuel injectors can start firing immediately, before the crankshaft even makes a full revolution. And of course the engine is already warmed up.
Interesting. That would imply that it really is in a kind of "sleep" mode, ready to self-start, and the first cylinder to fire would be the one in position to do so at the moment the engine was stopped. That's certainly consistent with what it sounds like -- the engine stops running, and then it's running again, with none of the normal startup sounds.
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Old 02-17-2020, 02:16 PM
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My 2019 Cherokee has a button I can hit to override the start-stop system, but I have to hit the button every time I first start up . If I stop and go into a store or something and shut it off, I have to disable it again when I start driving again.
Yes, they are all like this. The reason is that the EPA will only give full credit for the improved efficiency if they are designed this way with a "non-persistent" off switch.

There are hacks for some vehicles to be found online, and even companies that sell devices for some vehicles to override the electronics and allow a persistent off setting, so I assume it's not illegal to do so.
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Old 02-17-2020, 02:26 PM
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Even our city buses do this, at least the later models. I was disconcerted the first time it happened since I expected it to be hard to restart. Nope, the driver steps on the gas and it just goes.
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Old 02-17-2020, 06:22 PM
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My car model, a Volvo V60, has this as an option. If it's fitted, it has an extra battery and a heavy duty starter motor.
I rented a Chevrolet Impala in Los Angeles in 2013 which had the autostart function. The rev counter had a mark just below the 0 RPM point where the needle sat when it was stopped at lights or intersections, showing AutoStart. If the a/c was needed (Palm Springs in spring), the engine would keep running at stop lights.
Another time, in the Netherlands, I rented an Opel Astra, five speed manual, which had this feature. The engine would restart when you took your foot off the brake or as you released the clutch.
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Old 02-18-2020, 07:56 AM
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Yes, they are all like this. The reason is that the EPA will only give full credit for the improved efficiency if they are designed this way with a "non-persistent" off switch.

There are hacks for some vehicles to be found online, and even companies that sell devices for some vehicles to override the electronics and allow a persistent off setting, so I assume it's not illegal to do so.
There are some vehicles where there is no button to disable it (some SUVs by GM). I know a few people who hate the start-stop feature but they can't disable it like I can. When my Jeep was in the shop last year, my rental was a Chevy Equinox and the start-stop could not be disabled by a button.


I wonder if permanently disabling the start-stop feature will void the warranty? Some sites say yes, some sites say no.
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Old 02-18-2020, 08:15 AM
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Glad to know that's why a car mom and I rented to go to Nashville kept turning off! I don't have a huge problem with it, but egads, TELL THE PERSON if you're renting them a car that does this Most people by far are not driving cars with a feature like this, and can be caught off-guard if it were to suddenly happen without explanation. I generally avoid driving any cars other than my own if at all possible, and had I been in the driver's seat rather than my mom, I'd have had a mini panic attack.
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Old 02-18-2020, 09:11 AM
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Interesting. That would imply that it really is in a kind of "sleep" mode, ready to self-start, and the first cylinder to fire would be the one in position to do so at the moment the engine was stopped. That's certainly consistent with what it sounds like -- the engine stops running, and then it's running again, with none of the normal startup sounds.
I read an article a few years ago about a ďbreakthroughĒ in the stop-start technology. The control was precise enough that an engine could stop with one of the cylinders just past top dead center after the compression stroke. The fuel air mix was in the cylinder and compressed, ready to go. All the computer had to do to start 5he engine was fire that spark plug. No use of the starter or anything. I donít know if some/all of the manufacturers have implemented this, but there you go.
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Old 02-18-2020, 09:18 AM
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I drove one car like that about a year ago. I hated that function. One more thing to go wrong as far as I'm concerned. I was able to disable it with the push of a button, though.

My thinking exactly.
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Old 02-18-2020, 07:58 PM
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I drove one car like that about a year ago. I hated that function. One more thing to go wrong as far as I'm concerned. I was able to disable it with the push of a button, though.

My thinking exactly.
Yes, one more thing to go wrong. OTOH, thereís no wear on engine components while the car is stopped.
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Old 02-18-2020, 08:19 PM
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I drove one car like that about a year ago. I hated that function. One more thing to go wrong as far as I'm concerned.
What "one more thing" are you referring to? There is no additional component in the car to make this happen.
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Old 02-18-2020, 08:38 PM
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The Prius is a bit different, being a hybrid. It starts moving on battery power before the engine kicks in. On conventional cars with a start-stop system, the engine needs to start before the car can move.
Not being your average Prius driver, I'd often floor it when the light turned green, and accelerated faster than the hybrid system would support. So, maybe, but I'm not convinced.
Anyhow, with electronics, a car can react faster than a person can.
I have a new car, a 2020, and I haven't noticed it turn off the engine yet, so I can't tell for sure.
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Old 02-18-2020, 09:32 PM
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I have a new car, a 2020, and I haven't noticed it turn off the engine yet, so I can't tell for sure.
It's not required, so some cars may not have it. It was mostly put on cars to raise mileage rates to comply with CAFE requirements or their equivalent in other countries. AIUI, European cars got it several years before US ones did.
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Old 02-18-2020, 10:10 PM
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The Prius is a bit different, being a hybrid. It starts moving on battery power before the engine kicks in. On conventional cars with a start-stop system, the engine needs to start before the car can move.
Itís not different, really. Priuses can start moving on battery power alone, sure. But they donít have to. But even this distinction doesnít matteróa Prius needs to start its engine no matter how the car began rolling. Itís the same task.

As Voyager points out, Priuses will add IC power when the driver pushes the pedal past some threshold, even from a standstill.
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Old 02-18-2020, 11:34 PM
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I drove one car like that about a year ago. I hated that function. One more thing to go wrong as far as I'm concerned. I was able to disable it with the push of a button, though.

My thinking exactly.
As I said, cars have had this feature for many years now, and thereís no evidence that it causes more frequent repairs.
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Old 02-19-2020, 12:12 AM
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Almost all cars with this feature include a button somewhere to disable it, as others have noted. Sometimes, this is included in a "Sport" button or Sport mode, or listed in an electronic menu system.

This is one of several features that makes driving a modern passenger car a miserable experience. The others are the ubiquitous small-displacement, turbocharged four-cylinder engine, which generally sounds and feels like a strained lawnmower and comes with copious turbo lag, and the 8-speed (or more) automatic transmission that upshifts as early as possible and only bestows a downshift upon you with great reluctance.

Together, this is why I think EVs are going to take off much faster than anyone thinks, particularly in the premium / "entry luxury" market ($30,000+). They're completely quiet and smooth, and respond instantly and linearly. It's a vastly more pleasant experience than a small turbo 4-cylinder.
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Old 02-19-2020, 01:06 AM
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My Camry hybrid would just clear the garage backing out before the engine started. It would occasionally stop at red lights. My BMW has the option to turn off the auto stop-start. (You can also restart the engine by wiggling the steering wheel). My Tesla just goes.

Yes, autostart is one more feature to go wrong, but I assume it's built into the engine computer - so if the computer can't tell that the engine is not running, or that the button has been pushed, or that the engine is already turning - autostart is the least of your problems.

IMHO - the problem with ICE replacement will start to arrive when the cars become so few that finding a gas station will be the problem. (Not so much in town, but on extended highway trips and more out-of-the-way places). An electrical charger system is so simple, with computerized billing, they can be stuck anywhere - restaurant and hotel parking lots, shopping malls, etc. - and your own home. Gas stations need regular deliveries, need people to watch for theft (much harder to steal electricity unless you have a full charger unit of your own) and gas deliveries, the environmental risks of tank leaks, etc. - it will start to become less desirable a business as sales dwindle.
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Old 02-19-2020, 04:54 AM
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I’ve driven a few rental cars with auto shutoff. I don’t see what the objection is. It’s barely noticeable if there’s any noise from the radio or conversation.
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Old 02-19-2020, 09:18 AM
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Yes, one more thing to go wrong. OTOH, thereís no wear on engine components while the car is stopped.
It seems there are a finite number of cranks in a starter motor, though. Does this system not wear those little buggers out faster?
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Old 02-19-2020, 09:39 AM
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It seems there are a finite number of cranks in a starter motor, though. Does this system not wear those little buggers out faster?
Some/all of them just send a spark to whichever cylinder is at the top of the power stroke. No need for using the starter motor.
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Old 02-19-2020, 09:40 AM
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IMHO - the problem with ICE replacement will start to arrive when the cars become so few that finding a gas station will be the problem. (Not so much in town, but on extended highway trips and more out-of-the-way places).
Reprises many other threads but I believe that will be well past the life expectancy (or especially still driving expectancy) of the great majority of people posting here. In the US anyway. EV's becoming a significant share of market? Sure that could happen in next couple of decades. Not enough ICE's to support the gas station business is much too far off to think much about now IMO. Decades ago there was a small fraction as many cars as now, and it supported a national gas station network in the same size country.

On start-stop it's a funny combination of Ludditism and futurism IMO to complain about that while saying how convenient EV's are, which they actually aren't IMO as of now except for certain specialized use like always charge at home (everyone is free to have their consumer preference, as long as no ramp up in collective bribe/coercion measures to get people to buy EV's I have no problem with them). Or some people just complain about start-stop independent of EV's. I've had two start-stop equipped cars so far and don't see the complaint. 'One more thing to break' is not that useful an engineering metric actually.

On drivability of recent cars I found 2015 BMW 328i (8 speed, highly turbocharged 4) to be the most drivable I've had, just from POV of seamless and smooth. Transmission is excellent at choosing gears itself, car has plenty of power but avgs 37-38 mpg on long trips under my foot. I averaged just a couple more than that in a Toyota C-HR hybrid small SUV rental in Ireland, with dangerously weak acceleration to pass on two lane roads and shit handling. My current 2018 M2 (7 speed DCT, highly turbocharged 6) is more 'dramatic' in feel than the 328, always more going on terms of exhaust growl and feeling the shifts and engine braking effect if you let off the gas drive train wise, besides quite firm riding. And that's even when I drive nice and easy, as I do on crowded local roads. I only drive it hard on thinly trafficked winding roads, where its personality is exactly what I want. It also start-stops, a bit of a weird combination with the car's personality otherwise, but I don't see a problem with that, does save some gas.

Last edited by Corry El; 02-19-2020 at 09:43 AM.
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Old 02-19-2020, 10:37 AM
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modern cars with fuel injection and electronic ignition (and computerized fuel and timing controls) are far easier to start. Many now have a one tap push-button start rather than a push and hold to start. Thus, unlike the old carburetor system, they don't take a lot of time or extra gas to start, especially when the engine is still hot. Starting automatically when you take your foot off the brake (or wiggle the steering wheel) is fairly simple tech. So turning off when stopped is very fuel efficient. I should note that when the air conditioning or cabin heat warrants, the engine will start automatically once the heater/cooling has gone beyond optimum temperature.
The old carburetor days rule of thumb was that turning the engine off/on was roughly equivalent to idling for one minute, IIRC. So if you thought you'd be sitting still for more than a minute, it was most efficient to turn it off, but if you thought you'd be sitting still less than a minute, it was most efficient to just idle.

These days, it's clearly most efficient to turn it off if you'll be sitting still for almost any length of time.
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Old 02-19-2020, 10:50 AM
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modern cars with fuel injection and electronic ignition (and computerized fuel and timing controls) are far easier to start. Many now have a one tap push-button start rather than a push and hold to start. Thus, unlike the old carburetor system, they don't take a lot of time or extra gas to start, especially when the engine is still hot. Starting automatically when you take your foot off the brake (or wiggle the steering wheel) is fairly simple tech. So turning off when stopped is very fuel efficient. I should note that when the air conditioning or cabin heat warrants, the engine will start automatically once the heater/cooling has gone beyond optimum temperature.
The old carburetor days rule of thumb was that turning the engine off/on was roughly equivalent to idling for one minute, IIRC. So if you thought you'd be sitting still for more than a minute, it was most efficient to turn it off, but if you thought you'd be sitting still less than a minute, it was most efficient to just idle.

These days, it's clearly most efficient to turn it off if you'll be sitting still for almost any length of time.
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Old 02-19-2020, 11:06 AM
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Originally Posted by Absolute View Post
Almost all cars with this feature include a button somewhere to disable it, as others have noted. Sometimes, this is included in a "Sport" button or Sport mode, or listed in an electronic menu system.

This is one of several features that makes driving a modern passenger car a miserable experience. The others are the ubiquitous small-displacement, turbocharged four-cylinder engine, which generally sounds and feels like a strained lawnmower and comes with copious turbo lag, and the 8-speed (or more) automatic transmission that upshifts as early as possible and only bestows a downshift upon you with great reluctance.

Together, this is why I think EVs are going to take off much faster than anyone thinks, particularly in the premium / "entry luxury" market ($30,000+). They're completely quiet and smooth, and respond instantly and linearly. It's a vastly more pleasant experience than a small turbo 4-cylinder.
The VW Jetta I rented was exactly like you describe, with a turbocharged four-banger and an 8-speed transmission. But I found it great fun to drive and quite enjoyed the engine sound, although if I actually owned it, I'd worry about the stress and reliability of the engine over the long term. I believe there are are two engine options on the Jetta and from the feel of this one, it probably had the larger 2.0 liter one. My present car is about the same size and for the long term I appreciate its 2.7 liter 6-cylinder engine, which has been totally reliable for years, always super smooth, and never sounds stressed. I believe it's just a three-speed transmission with overdrive, but the overdrive is a major feature for fuel economy and reduced engine wear.
  #42  
Old 02-19-2020, 12:40 PM
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About starting by just firing a plug/knowing which cylinder was ready. How long does the compression hold in the cylinder? I would think that the pressure would leak out just sitting there and have no compression when fired.
  #43  
Old 02-19-2020, 02:04 PM
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Originally Posted by Capn Carl View Post
Iíve driven a few rental cars with auto shutoff. I donít see what the objection is. Itís barely noticeable if thereís any noise from the radio or conversation.
The only problem I foresee, and I know I'll catch flak for this, but on cold mornings I want to start my car and let it run for five or ten minutes to warm up. It allows me to enter the vehicle without being miserable, it lets me clear the windshield with a brush instead of a scraper (or even just a flick of the wipers), and as far as I'm concerned it isn't inefficient at all. For those few minutes I don't want the car to take me anywhere, I want it to be a space heater, and space heaters are always 100% efficient. MPG can wait until I'm on the road.

I've never driven a car that shuts off automatically, but as long as I can override that feature until the car is warm, I'm okay with it. Otherwise, we'll have a problem.
  #44  
Old 02-19-2020, 02:19 PM
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Originally Posted by DrCube View Post
I've never driven a car that shuts off automatically, but as long as I can override that feature until the car is warm, I'm okay with it. Otherwise, we'll have a problem.
You shouldn't have to override it for that reason. This feature only works when the engine is warm, so it's not going to be shutting off while you're warming it up.
  #45  
Old 02-19-2020, 02:33 PM
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Originally Posted by Corry El View Post
'One more thing to break' is not that useful an engineering metric actually.
Indeed. By that logic the world's most reliable car should be something like a bare bones 1955 VW Beetle. After all, things like automatic transmissions, power steering, power windows, air conditioning, heaters, radios, liquid cooling, etc. are all just more things that can potentially break.
  #46  
Old 02-19-2020, 03:49 PM
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I used to have a engine monitor called DashHawk that would display various engine parameters like boost/vacuum, intake air temperature, and engine load. IIRC an 2008 Mazdaspeed3 would take about 30% engine load to just idle in neutral. In a modern fuel-injected computer-controlled engine, idling at a stoplight actually burns far more fuel than coasting downhill or driving on a level surface at constant speed.
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Old 02-19-2020, 03:52 PM
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Originally Posted by dtilque View Post
You shouldn't have to override it for that reason. This feature only works when the engine is warm, so it's not going to be shutting off while you're warming it up.
I'm not talking about warming up the engine. That only takes a minute or two anyway. I'm talking about warming up the passenger cabin and windshields when the outside temp is below freezing.
  #48  
Old 02-19-2020, 06:20 PM
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IIRC an 2008 Mazdaspeed3 would take about 30% engine load to just idle in neutral. In a modern fuel-injected computer-controlled engine, idling at a stoplight actually burns far more fuel than [...] driving on a level surface at constant speed.
[Emphasis added]

This isnít true at all. Respectfully, you may have misunderstand what ďloadĒ means in this contextóitís not the same thing as power.

When your engine idles, it feeds in enough fuel and air to keep the engine at about 1000-1400 RPM while still overcoming friction and driving the alternator and any other belt-driven accessories.

When youíre driving down a flat highway at 55 mph, your engine has to do all that and overcome wind and rolling resistance.

Combustion efficiency varies with RPM, and most four-cycle and Miller-cycle engines have significant pumping losses at small throttle openings. And while those losses are large on a relative basis, the power required to idle is low enough that the pumping losses are small in absolute terms.

It definitely takes more fuel to drive at a steady speed on flat ground than it does to idle.

Last edited by EdelweissPirate; 02-19-2020 at 06:24 PM. Reason: Copy editing
  #49  
Old 02-19-2020, 08:17 PM
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In a modern fuel-injected computer-controlled engine, idling at a stoplight actually burns far more fuel than [...] driving on a level surface at constant speed.
This is...implausible.
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  #50  
Old 02-19-2020, 10:42 PM
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Originally Posted by Absolute View Post
This is...implausible.
Well, the miles-per-gallon is certainly worse.
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