4 ms·

> the lithium battery allows officers to power the accessories without having the engine run as much, which reduces fuel consumption further and improves wear a

by p1mrx 3y ago

> the lithium battery allows officers to power the accessories without having the engine run as much, which reduces fuel consumption further and improves wear and maintenance costs. IMHO, all gas-powered SUVs should be hybrids, especially since the EPA mandates stopping the engine while stationary. A hybrid would significantly reduce the pedal-to-wheels latency and keep the A/C running at stoplights.

pmontra 3y ago
> the EPA is mandating that the engine stop while the vehicle is stationary How could they use AC and heating with traditional cars, when they had to stay stationary for a long time in summer or winter?
- kjkjadksj 3y ago
  You get like 30 seconds of cold air before the compressor being off is evident. A lot of people turn this “feature” off if they can.
- p1mrx 3y ago
  I'm not sure exactly what the rule says. I've heard stories of people buying a modern SUV, and needing to push a button on every trip, to disable the start/stop feature. I've also heard of people making a little motorized arm that pushes the button automatically. Edit: It's not strictly mandatory. See page 3 of https://www.govinfo.gov/content/pkg/CFR-2014-title40-vol19/pdf/CFR-2014-title40-vol19-sec86-1869-12.pdf https://www.govinfo.gov/content/pkg/CFR-2014-title40-vol19/p...
  - Kon-Peki 3y ago
    > It's not strictly mandatory. My understanding is that if the automaker uses it during the EPA fuel economy test, it must be enabled every time the car starts. If not, the automaker can choose to have it remember your preferences.
- RandallBrown 3y ago
  I'm only assuming that both of my brand new cars are EPA compliant (they may not be) but they'll just turn back on if it's been long enough to get too cold or warm.
- Modified3019 3y ago
  My pickup engine stops when I come to a stop, usually, but after some time will start up again if power is needed to continue to run the AC and electronics. Warming up the truck in the winter isn’t an issue, it starts and runs like normal.
- kj4ips 3y ago
  Heat generally continues to work for quite a while, because there's quite a lot of thermal mass involved. As for the AC, some vehicles have reserve pressure canister that can keep it going for a little bit before they have to cycle back on.
aftbit 3y ago
My dad's Subaru has saved a total of 7 minutes of runtime thanks to this misfeature over the past year, in exchange for many extra cycles on the starter. What an absolutely silly idea.
- RandallBrown 3y ago
  He can turn it off if he wants. I've saved considerably more time (maybe like 20-30 minutes?) in just a few months of having my new Subaru.
  - ultrarunner 3y ago
    It resets itself back on (by law) every time you restart the vehicle. A couple days ago mine failed to restart itself, instead shifting into neutral (!) and rolling partially into the intersection I had intended to pull out into. It wouldn't shift into park because it wasn't "on" (?) but also wouldn't turn "on" (!?) as traffic started to barrel down on me. I'm honestly not sure what sequence of pushing the "on/acc/start/off" button, the "park" button, and "drive" button got it back running, but eventually I was able to go. It was a somewhat stressful experience, but I guess I saved ~10-15 seconds of idling trying to leave work?
    - deleted 3y ago
      [deleted]
    - giantg2 3y ago
      "It resets itself back on (by law) every time you restart the vehicle" That's what internet searches and fuse pullers are for. "but I guess I saved ~10-15 seconds of idling" That's where the calculations get tricky. There's usually a time limit for which it's less efficient to stop the engine (about 4-7 seconds). So to calculate fuel savings, you actually should only count idle fuel rate times the number of seconds above that cutoff, then you also have to account for less efficient stops under that rate (maybe just subtract them from your seconds above so you get a net seconds beyond breakeven mark). I'm not sure any the systems track it that way, it's just how much overall time the car spent in the stopped mode.
giantg2 3y ago
Instead of all SUVs being mandated this way, we should rather mandate all vehicles that perform similar functions (police, security, mail, fleet vehicles) be hybrid or electric. I think that would place those batteries in the most useful places - vehicles that have short trips, stop and start a lot, are used every weekday for most of the day, and log an average annual mileage over 50% higher than personal vehicles.
patrick451 3y ago
I hate this anti-feature. It makes the vehicle really sluggish, adding seconds to every takeoff. It's completely nerve wracking making an unprotected left when you have to wait for the engine to start before the vehicle even starts moving. It also strikes me as a sub-optimal greedy optimization. If every car has this feature, then overall takeoff time in a long line of cars at a light should be expected to increase, and I would imagine the accordion gets worse and congestion gets worse. I wonder if anybody has studied this tradeoff. Edit: it may be that people who drive a car with this feature overcome the delay by taking pre-emptive action (I have only driven a car like this as a rental), but it would still be interesting to see a study.
- jacobr1 3y ago
  My Toyota turns the engine back on as soon as you start releasing the break. By the time I'm pushing down the gas pedal, it is ready to go. It still is annoying when I want A/C to cool things down, but overall I don't find it cause much of start latency issue.
- sidewndr46 3y ago
  is this why I've noticed an uptick in drivers that seem to take a last minute left turn in front of me? I wind up braking as hard as possible to avoid an accident.
- gambiting 3y ago
  >>It makes the vehicle really sluggish, adding seconds to every takeoff. This is completely 100% solved by modern hybrids and PHEVS where the electric motor is directly on the axle or on the transmssion - the car starts moving instantly when you press the accelerator with zero delay. I strongly encourage trying a model like that for yourself - it literally makes this entire system finally work as it should.
throw7 3y ago
I will never buy a vehicle that shuts off the engine at idle. It is the dumbest most annoying misfeature ever.
- mock-possum 3y ago
  Why?
- timtom39 3y ago
  It is not a feature it was forced down by the EPA :/ I have such an SUV and a $20 part wired into the fuse box fixes it.
  - rokkitmensch 3y ago
    Technically not forced by the EPA, strictly speaking optional with the caveat that if you claim a MPG rating for a car, (I believe) it must be enabled every vehicle start.
- gambiting 3y ago
  That's such a weird hill to die on. It's literally not a problem for any competent driver, not to mention that in modern cars this is completely solved by the addition of electric motors on the drivetrain so there is literally no delay whatsoever. Calling it the "dumbest most annoying" feature when touchscreens in cars exist is just weird.
- rokkitmensch 3y ago
  Just scour the market for the two manual models that are left, I'm pretty sure this feature won't show up on standards for several years yet.
AtlasBarfed 3y ago
Um, let's not forget your basic city cop is crawling around the city and doing stop-and-go all day. The regenerative braking and all-electric modes will bypass huge amounts of "city driving" mpg losses. City cops are the big reason we need PHEVs with 50 mile all-electric ranges. They would probably do 90% of their shift on all-electric, and the gas motor will recharge what they don't need. In a parallel universe, Gore won the 2000 election, and got legislation through that forced PHEV technology to virtually all consumer segments within a decade. By now we would have electrified 70-80% of daily driving miles, cut emissions, and probably had cheaper cars in the process, and bankrupted the Saudis and Russians. There also were various patents around inside-out rotaries and other compact higher-output engines about 10 years ago that would have made perfect recharger/range extenders for a PHEV.
davidbanham 3y ago
All our fire trucks are fitted with isolation switches. We either leave the engine idling, or we stop the engine then physically disconnect the batteries. The reason is that all the radios and gear drain the battery so quickly without the engine running. Having a hybrid style setup that cut the engine in or out as required when stopped on scene would be awesome.

by p1mrx 3y ago

pmontra 3y ago

> the EPA is mandating that the engine stop while the vehicle is stationary How could they use AC and heating with traditional cars, when they had to stay stationary for a long time in summer or winter?

kjkjadksj 3y ago
You get like 30 seconds of cold air before the compressor being off is evident. A lot of people turn this “feature” off if they can.
p1mrx 3y ago
I'm not sure exactly what the rule says. I've heard stories of people buying a modern SUV, and needing to push a button on every trip, to disable the start/stop feature. I've also heard of people making a little motorized arm that pushes the button automatically. Edit: It's not strictly mandatory. See page 3 of https://www.govinfo.gov/content/pkg/CFR-2014-title40-vol19/pdf/CFR-2014-title40-vol19-sec86-1869-12.pdf https://www.govinfo.gov/content/pkg/CFR-2014-title40-vol19/p...
- Kon-Peki 3y ago
  > It's not strictly mandatory. My understanding is that if the automaker uses it during the EPA fuel economy test, it must be enabled every time the car starts. If not, the automaker can choose to have it remember your preferences.
RandallBrown 3y ago
I'm only assuming that both of my brand new cars are EPA compliant (they may not be) but they'll just turn back on if it's been long enough to get too cold or warm.
Modified3019 3y ago
My pickup engine stops when I come to a stop, usually, but after some time will start up again if power is needed to continue to run the AC and electronics. Warming up the truck in the winter isn’t an issue, it starts and runs like normal.
kj4ips 3y ago
Heat generally continues to work for quite a while, because there's quite a lot of thermal mass involved. As for the AC, some vehicles have reserve pressure canister that can keep it going for a little bit before they have to cycle back on.

aftbit 3y ago

My dad's Subaru has saved a total of 7 minutes of runtime thanks to this misfeature over the past year, in exchange for many extra cycles on the starter. What an absolutely silly idea.

RandallBrown 3y ago
He can turn it off if he wants. I've saved considerably more time (maybe like 20-30 minutes?) in just a few months of having my new Subaru.
- ultrarunner 3y ago
  It resets itself back on (by law) every time you restart the vehicle. A couple days ago mine failed to restart itself, instead shifting into neutral (!) and rolling partially into the intersection I had intended to pull out into. It wouldn't shift into park because it wasn't "on" (?) but also wouldn't turn "on" (!?) as traffic started to barrel down on me. I'm honestly not sure what sequence of pushing the "on/acc/start/off" button, the "park" button, and "drive" button got it back running, but eventually I was able to go. It was a somewhat stressful experience, but I guess I saved ~10-15 seconds of idling trying to leave work?
  - deleted 3y ago
    [deleted]
  - giantg2 3y ago
    "It resets itself back on (by law) every time you restart the vehicle" That's what internet searches and fuse pullers are for. "but I guess I saved ~10-15 seconds of idling" That's where the calculations get tricky. There's usually a time limit for which it's less efficient to stop the engine (about 4-7 seconds). So to calculate fuel savings, you actually should only count idle fuel rate times the number of seconds above that cutoff, then you also have to account for less efficient stops under that rate (maybe just subtract them from your seconds above so you get a net seconds beyond breakeven mark). I'm not sure any the systems track it that way, it's just how much overall time the car spent in the stopped mode.

giantg2 3y ago

Instead of all SUVs being mandated this way, we should rather mandate all vehicles that perform similar functions (police, security, mail, fleet vehicles) be hybrid or electric. I think that would place those batteries in the most useful places - vehicles that have short trips, stop and start a lot, are used every weekday for most of the day, and log an average annual mileage over 50% higher than personal vehicles.

patrick451 3y ago

I hate this anti-feature. It makes the vehicle really sluggish, adding seconds to every takeoff. It's completely nerve wracking making an unprotected left when you have to wait for the engine to start before the vehicle even starts moving. It also strikes me as a sub-optimal greedy optimization. If every car has this feature, then overall takeoff time in a long line of cars at a light should be expected to increase, and I would imagine the accordion gets worse and congestion gets worse. I wonder if anybody has studied this tradeoff. Edit: it may be that people who drive a car with this feature overcome the delay by taking pre-emptive action (I have only driven a car like this as a rental), but it would still be interesting to see a study.

jacobr1 3y ago
My Toyota turns the engine back on as soon as you start releasing the break. By the time I'm pushing down the gas pedal, it is ready to go. It still is annoying when I want A/C to cool things down, but overall I don't find it cause much of start latency issue.
sidewndr46 3y ago
is this why I've noticed an uptick in drivers that seem to take a last minute left turn in front of me? I wind up braking as hard as possible to avoid an accident.
gambiting 3y ago
>>It makes the vehicle really sluggish, adding seconds to every takeoff. This is completely 100% solved by modern hybrids and PHEVS where the electric motor is directly on the axle or on the transmssion - the car starts moving instantly when you press the accelerator with zero delay. I strongly encourage trying a model like that for yourself - it literally makes this entire system finally work as it should.

throw7 3y ago

I will never buy a vehicle that shuts off the engine at idle. It is the dumbest most annoying misfeature ever.

mock-possum 3y ago
Why?
timtom39 3y ago
It is not a feature it was forced down by the EPA :/ I have such an SUV and a $20 part wired into the fuse box fixes it.
- rokkitmensch 3y ago
  Technically not forced by the EPA, strictly speaking optional with the caveat that if you claim a MPG rating for a car, (I believe) it must be enabled every vehicle start.
gambiting 3y ago
That's such a weird hill to die on. It's literally not a problem for any competent driver, not to mention that in modern cars this is completely solved by the addition of electric motors on the drivetrain so there is literally no delay whatsoever. Calling it the "dumbest most annoying" feature when touchscreens in cars exist is just weird.
rokkitmensch 3y ago
Just scour the market for the two manual models that are left, I'm pretty sure this feature won't show up on standards for several years yet.

AtlasBarfed 3y ago

Um, let's not forget your basic city cop is crawling around the city and doing stop-and-go all day. The regenerative braking and all-electric modes will bypass huge amounts of "city driving" mpg losses. City cops are the big reason we need PHEVs with 50 mile all-electric ranges. They would probably do 90% of their shift on all-electric, and the gas motor will recharge what they don't need. In a parallel universe, Gore won the 2000 election, and got legislation through that forced PHEV technology to virtually all consumer segments within a decade. By now we would have electrified 70-80% of daily driving miles, cut emissions, and probably had cheaper cars in the process, and bankrupted the Saudis and Russians. There also were various patents around inside-out rotaries and other compact higher-output engines about 10 years ago that would have made perfect recharger/range extenders for a PHEV.

davidbanham 3y ago

All our fire trucks are fitted with isolation switches. We either leave the engine idling, or we stop the engine then physically disconnect the batteries. The reason is that all the radios and gear drain the battery so quickly without the engine running. Having a hybrid style setup that cut the engine in or out as required when stopped on scene would be awesome.