EPA rule rollback, effects?

[kalvado]

My understanding was that the primary benefits were: (A) vehicles with Stop/Start functionality have significantly reduced emissions at the intersection itself while stopped and not idling (mentioned in a previous post); and (B) widespread usage reduces the aggregate number of vehicles stopped-and-idling at an intersection (ergo, lots of vehicles causing emissions at essentially the same location while not creating a winddraft that [circulates] the noxious emissions.

Maybe that was the rationale -- reduced emissions at the intersection itself with all the vehicles present.

Pretty questionable idea as even mild wind would dissipate things fairly quickly.

[Max Rockatansky]

I'm curious, does anyone have general fuel economy savings statistics on cylinder deactivation?  That was a thing on the L99 V8 I had in my 2010 Camaro.  I believe it only altered the highway rating for that car maybe by 1 MPG over the manual transmission equipped LS3?  I'd be curious to see how effective that was versus start/stop technology.

[kalvado]

I'm curious, does anyone have general fuel economy savings statistics on cylinder deactivation?  That was a thing on the L99 V8 I had in my 2010 Camaro.  I believe it only altered the highway rating for that car maybe by 1 MPG over the manual transmission equipped LS3?  I'd be curious to see how effective that was versus start/stop technology.

Just looked at some papers.. this is all cycle dependent. Cylinder deactivation can also work when the vehicle is in motion, but doesn't need all the engine power. Start-stop seems limited to stops, but provides deeper cuts.
So it may boil down to how long you wait at lights, and how much of crawling at 3 mph you encounter.

[Scott5114]

The first religion was some guy telling others that he made the sun come up, the rain fall, the crops grow, etc. and if everyone didn't do as he said, he would stop these.

Sadly there are those that still fall for this act. 

Sadly, there are those that still fall for misinformation about negative human impacts on the environment.

The harmfulness of exhaust emissions is easily measured.  Just close a garage, keep a gasoline engine running and measure the effects of what happens to all life forms contained within an hour or so later.

Nevada building codes require garages to include vents to outside, presumably because people decided to run this experiment after a losing night on the Strip.

[Rothman]

Visited my sister in Madison WI when daytime highs were 0 to +5 F. How do you like the stupid thing causing the engine to stop along with the heater when you are at a light?

Hm.  I haven't had the heater shut off at idling.  I usually have it set to auto on the thermostat, though.

Actually the heater did not shut off -- just put out cold air -- stopped heating the car.

Bad car.

[TheHighwayMan3561]

Visited my sister in Madison WI when daytime highs were 0 to +5 F. How do you like the stupid thing causing the engine to stop along with the heater when you are at a light?

I mean, as someone whose car does do this...those of us who live here probably barely notice? I imagine if I lived in FL/TX/whatever and the AC shut off momentarily while the car was stopped in summer, I would notice it a lot more than a local.

[Beltway]

Visited my sister in Madison WI when daytime highs were 0 to +5 F. How do you like the stupid thing causing the engine to stop along with the heater when you are at a light?

Hm.  I haven't had the heater shut off at idling.  I usually have it set to auto on the thermostat, though.

Actually the heater did not shut off -- just put out cold air -- stopped heating the car.

Bad car.

So how does the heater heat the air in 0 F weather when the motor is not running?

Visited my sister in Madison WI when daytime highs were 0 to +5 F. How do you like the stupid thing causing the engine to stop along with the heater when you are at a light?

I mean, as someone whose car does do this...those of us who live here probably barely notice? I imagine if I lived in FL/TX/whatever and the AC shut off momentarily while the car was stopped in summer, I would notice it a lot more than a local.

I want it to stay running.

Zero is a lot farther from room temperature than 95.

[TheHighwayMan3561]

Visited my sister in Madison WI when daytime highs were 0 to +5 F. How do you like the stupid thing causing the engine to stop along with the heater when you are at a light?

I mean, as someone whose car does do this...those of us who live here probably barely notice? I imagine if I lived in FL/TX/whatever and the AC shut off momentarily while the car was stopped in summer, I would notice it a lot more than a local.

I want it to stay running.

Zero is a lot farther from room temperature than 95.

I was merely answering the question, not saying it's right or wrong.

[formulanone]

I'm curious, does anyone have general fuel economy savings statistics on cylinder deactivation?  That was a thing on the L99 V8 I had in my 2010 Camaro.  I believe it only altered the highway rating for that car maybe by 1 MPG over the manual transmission equipped LS3?  I'd be curious to see how effective that was versus start/stop technology.

Just looked at some papers.. this is all cycle dependent. Cylinder deactivation can also work when the vehicle is in motion, but doesn't need all the engine power. Start-stop seems limited to stops, but provides deeper cuts.
So it may boil down to how long you wait at lights, and how much of crawling at 3 mph you encounter.

If anything, you'd need a greater percentage of engine power when accelerating (even at a leisurely or moderate rate) so cylinder deactivation does not tend to occur. Newton's First Law.

When you're at or near cruising speed for a certain amount of time, you only need a smaller percentage of available power (usually 5-10%) unless the vehicle is maxing out at terminal velocity; ergo, Newton's Third Law. There aren't many vehicles like this, the days of sub-100hp engines tied to an inefficient 3/4 speed transmission are long gone in the U.S. 

Like engine start-stop technology, it's not always perfectly implemented. It's all so automakers can claim another 0.5-2.0 mpg in most testing situations. If {Auto Brand} gets 20,000 vehicles/year to save a single mile per gallon, they can offer a limited model with 5000 units which can then have 4mpg worse fuel economy (if they wanted to), so as long as their total fleet of light trucks meets an average limit.

Push-button ignition starting has nothing to do with any EPA feature.

[1995hoo]

Europeans still buy a lot of stick shift cars (though fewer than in the past), and even those have a stop/start system. Which is kind of pointless, you need to put the manual gear in neutral for it to take effect, and it turns the engine off. It restarts once you press the clutch.

I don't think many people put a manual car in neutral at a traffic signal, so this stop/start system has no value, other than companies selling batteries, because the batteries on these systems are considerably more expensive. I had to replace mine one time and the cost was 3 times that of a regular car battery.

You think we sit there with our foot on the clutch? I've always shifted into neutral precisely so I don't need to keep my foot on the clutch. That's also why European traffic lights are designed correctly (unlike American lights) to tell you when they're about to turn green—it's so you can shift into gear and be ready to move, under the assumption people shift to neutral while waiting.

[Rothman]

Visited my sister in Madison WI when daytime highs were 0 to +5 F. How do you like the stupid thing causing the engine to stop along with the heater when you are at a light?

Hm.  I haven't had the heater shut off at idling.  I usually have it set to auto on the thermostat, though.

Actually the heater did not shut off -- just put out cold air -- stopped heating the car.

Bad car.

So how does the heater heat the air in 0 F weather when the motor is not running?

What my car does: Not kill the source of the heat when you idle/stop.

Like I said, bad car.

[Chris]

Europeans still buy a lot of stick shift cars (though fewer than in the past), and even those have a stop/start system. Which is kind of pointless, you need to put the manual gear in neutral for it to take effect, and it turns the engine off. It restarts once you press the clutch.

I don't think many people put a manual car in neutral at a traffic signal, so this stop/start system has no value, other than companies selling batteries, because the batteries on these systems are considerably more expensive. I had to replace mine one time and the cost was 3 times that of a regular car battery.

You think we sit there with our foot on the clutch? I've always shifted into neutral precisely so I don't need to keep my foot on the clutch. That's also why European traffic lights are designed correctly (unlike American lights) to tell you when they're about to turn green—it's so you can shift into gear and be ready to move, under the assumption people shift to neutral while waiting.

I doubt if most people shift to neutral in a manual at a traffic light in Europe. I've never seen anyone doing this in the Netherlands, where manuals were 80-90% of the cars for a long time. Drivers sit with the foot on the clutch.

The European traffic light sequence varies by country, a lot of countries don't have a yellow-before-green phase.

With EVs and hybrid vehicles, automatic transmission is quickly gaining ground. Cars were taxed on CO2 emissions and manuals were often cheaper.

[vdeane]

Europeans still buy a lot of stick shift cars (though fewer than in the past), and even those have a stop/start system. Which is kind of pointless, you need to put the manual gear in neutral for it to take effect, and it turns the engine off. It restarts once you press the clutch.

I don't think many people put a manual car in neutral at a traffic signal, so this stop/start system has no value, other than companies selling batteries, because the batteries on these systems are considerably more expensive. I had to replace mine one time and the cost was 3 times that of a regular car battery.

You think we sit there with our foot on the clutch? I've always shifted into neutral precisely so I don't need to keep my foot on the clutch. That's also why European traffic lights are designed correctly (unlike American lights) to tell you when they're about to turn green—it's so you can shift into gear and be ready to move, under the assumption people shift to neutral while waiting.

I doubt if most people shift to neutral in a manual at a traffic light in Europe. I've never seen anyone doing this in the Netherlands, where manuals were 80-90% of the cars for a long time. Drivers sit with the foot on the clutch.

The European traffic light sequence varies by country, a lot of countries don't have a yellow-before-green phase.

With EVs and hybrid vehicles, automatic transmission is quickly gaining ground. Cars were taxed on CO2 emissions and manuals were often cheaper.

I also shift to neutral a lot of the time at lights, and I can't imagine why anyone wouldn't.  If I'm going to be sitting for 30 seconds to three minutes (depending on the light), why should I keep my foot on the clutch the whole time rather than putting the car into neutral and resting my foot?  The only reason I keep my other foot on the brake instead of setting the parking/emergency brake is so I keep the brake lights on to avoid confusing other cars.  Of course, it helps that I'm quite familiar with the lights in my local area, and I have a good idea of when my phase is coming up.  I do this less in unfamiliar territory, but still, if there are at least a couple cars in front of me, there's little delay in doing so, even without an indication on the light that the green is coming.

And this is on my Civic, which has a relatively easy clutch.  My Accord's clutch had enough resistance that not going into neutral at some of the long lights around here would really suck.  Although I've been flirting with the idea of getting an automatic for my next car (if/when I ever do - I have no plans to at the moment, and with how computerized cars have gotten, I'd really rather not).  My shifting skills never recovered to their pre-COVID level and dealing with the clutch is more annoying than it was when I was younger.  On the other hand, driving automatics always feel like something's missing, and I like the built-in anti-theft system the manual transmission adds by virtue of so many people not knowing how to drive them.

[1995hoo]

And then there was this:

I compulsively shake my gearshift while in neutral, as if this is going to keep it loose or something.

I do that when I come to a stop, but I no longer sit there doing it while I wait for the light to turn.

In college a female friend asked why I shook the gearshift so much. I told her it was because I like to play with my stick in traffic.

....

[Chris]

I also shift to neutral a lot of the time at lights, and I can't imagine why anyone wouldn't.  If I'm going to be sitting for 30 seconds to three minutes (depending on the light), why should I keep my foot on the clutch the whole time rather than putting the car into neutral and resting my foot?

I suppose signal phases are shorter over here. I do put it in neutral at a railroad crossing or a drawbridge opening, but not at a traffic signal. Most of the time the waiting time at a signal is under 30 - 40 seconds, and in many cases under 15 seconds. 3 minutes waiting would be considered extremely long, I don't know any signal in my area that takes 3 minutes to go through a full cycle.

I've never ridden with anyone who put their manual in neutral at a traffic light. A little research shows that driving schools teach student drivers to put it in neutral for longer waits, not brief stops at traffic signals.

[seicer]

On the elimination of the stop/start, good. Auto stop/start systems produced modest, situational gains, not transformative ones. The effects were measurable but limited, reducing fuel consumption by minuscule amounts and CO₂, NOₓ, and particulates by proportionally smaller amounts. It was alow-cost regulatory tool to shave fleet-average CO₂ numbers.

On my 2022 Subaru Outback Wilderness, I get roughly 21 MPG in real-world driving. Over my ownership (April 2022-February 2026), I've saved a whopping 6.2 gallons of fuel... or $5-7 per year. It shuts off, but often restarts within seconds. It shakes hard upon restart because of the CVT and torque converter coupling, the horizontally opposed engine layout, and the heavier driveline. It's not a refined system.

At least in a software update two years ago, I can shut off auto stop/start by pressing a button on the screen each time, but I've invested in a small dongle to bypass the system completely.

[1995hoo]

I also shift to neutral a lot of the time at lights, and I can't imagine why anyone wouldn't.  If I'm going to be sitting for 30 seconds to three minutes (depending on the light), why should I keep my foot on the clutch the whole time rather than putting the car into neutral and resting my foot?

I suppose signal phases are shorter over here. I do put it in neutral at a railroad crossing or a drawbridge opening, but not at a traffic signal. Most of the time the waiting time at a signal is under 30 - 40 seconds, and in many cases under 15 seconds. 3 minutes waiting would be considered extremely long, I don't know any signal in my area that takes 3 minutes to go through a full cycle.

I've never ridden with anyone who put their manual in neutral at a traffic light. A little research shows that driving schools teach student drivers to put it in neutral for longer waits, not brief stops at traffic signals.

If I hit the light leaving my neighborhood right after it turns red, I'll have to wait more than two minutes except at night. No way am I sitting there with my foot on the clutch for that amount of time.

[vdeane]

I also shift to neutral a lot of the time at lights, and I can't imagine why anyone wouldn't.  If I'm going to be sitting for 30 seconds to three minutes (depending on the light), why should I keep my foot on the clutch the whole time rather than putting the car into neutral and resting my foot?

I suppose signal phases are shorter over here. I do put it in neutral at a railroad crossing or a drawbridge opening, but not at a traffic signal. Most of the time the waiting time at a signal is under 30 - 40 seconds, and in many cases under 15 seconds. 3 minutes waiting would be considered extremely long, I don't know any signal in my area that takes 3 minutes to go through a full cycle.

I've never ridden with anyone who put their manual in neutral at a traffic light. A little research shows that driving schools teach student drivers to put it in neutral for longer waits, not brief stops at traffic signals.

Interesting.  Signals with a light cycle that's only 15 seconds long are quite rare over here.  A pedestrian "don't walk" phase alone is mandated to be longer pretty much everywhere to maintain accessibility for the elderly and disabled.  And such isn't very beneficial to motorists on the main road, either.  Do Europeans not have an expectation of hitting a "green wave" or of not hitting every light red, or are signals somehow smarter over there?

[Beltway]

So how does the heater heat the air in 0 F weather when the motor is not running?

What my car does: Not kill the source of the heat when you idle/stop.
Like I said, bad car.

Heaters are normally heated by hot radiator water. In zero degree weather when that stops flowing and/or cools, the air that comes out quickly gets cold.

[Rothman]

So how does the heater heat the air in 0 F weather when the motor is not running?

What my car does: Not kill the source of the heat when you idle/stop.
Like I said, bad car.

Heaters are normally heated by hot radiator water. In zero degree weather when that stops flowing and/or cools, the air that comes out quickly gets cold.

Well...yes.  So...bad car...

[Beltway]

So how does the heater heat the air in 0 F weather when the motor is not running?

What my car does: Not kill the source of the heat when you idle/stop.
Like I said, bad car.

Heaters are normally heated by hot radiator water. In zero degree weather when that stops flowing and/or cools, the air that comes out quickly gets cold.

Well...yes.  So...bad car...

There may well be a switch somewhere, I looked, but it was a rental car and I only had it for a few days.

My own car has the button in plain sight.

[kphoger]

Since we're talking about stickshifts and red lights...  I downshift to third gear (second gear if it's on a downhill), then put it into neutral as soon as the tachometer drops to around 1000rpm or so (approximately the same as idling).  I keep it in neutral until just before I'm ready to go again.  If I'm first in line, then that's when cross-traffic gets a red.  If I'm third or fourth in line, then it's when my light turns green.  Only if I'm confident my stop will only be a second or two do I keep it in gear.  Keeping the clutch pedal depressed unnecessarily causes some undue wear on the throw-out bearing (and my car already shows some signs of a worn throw-out bearing anyway).

[mgk920]

How close was the USA to adopting the European one or two second 'yellow/red' phase in traffic signal cycles due to them?

Mike

[hbelkins]

I was glad to see that someone finally acknowledged that someone had conflated the start-stop feature (bad) with pushbutton starting (indifferent).

[The_Ginger]

I was glad to see that someone finally acknowledged that someone had conflated the start-stop feature (bad) with pushbutton starting (indifferent).

I had noticed the same.