How L "gear" works

Hi everyone,

I'm a new 2014 Spark EV owner as of last Saturday and have been loving every second of driving around the city in it and perusing this awesome forum!

I had a quick question if anyone happens to have the answer to it...

Since there are no actual gears on our car, does anyone know how driving in L works as opposed to D? I was reading tips to conserve energy and it says to drive in L during stop and go traffic which I did today but I noticed that there didn't seem to be much of a difference while I accelerated. I noticed that when I let go of the accelerator l, the car began to regen as if I was pressing lightly on the brakes. So I guess my question is, is there any difference while accelerating at all, and does driving in L use the brakes at all while slowing down?

Thanks for the help and I'm happy to be part of the EV and Spark EV fam now!

jerb2k said:

Hi everyone,

I'm a new 2014 Spark EV owner as of last Saturday and have been loving every second of driving around the city in it and perusing this awesome forum!

I had a quick question if anyone happens to have the answer to it...

Since there are no actual gears on our car, does anyone know how driving in L works as opposed to D? I was reading tips to conserve energy and it says to drive in L during stop and go traffic which I did today but I noticed that there didn't seem to be much of a difference while I accelerated. I noticed that when I let go of the accelerator l, the car began to regen as if I was pressing lightly on the brakes. So I guess my question is, is there any difference while accelerating at all, and does driving in L use the brakes at all while slowing down?

Thanks for the help and I'm happy to be part of the EV and Spark EV fam now!

Click to expand...

I drive in L all of the time to reduce the wear and tear on the brakes while using the deceleration energy to recharge the battery rather than waste energy with the brakes. It works great - especially going down long road grades. Usually, I do not apply the brakes until just before the car stops or I have to quickly brake for the car in front of me. In L, Regen is significantly increased during deceleration and it has no affect on acceleration. In D you can feel the car "coast" when you let off of the accelerator. In L you can feel the car slow down significantly. Note: after a full charge and starting out in L, you will not feel the regen braking for a mile or two. This is because the battery is fully charged and regen is temporarily disabled.

One suggestion: Contact you dealer and have them reprogram the brake light software so there is no delay in turning on the rear brake lights when you back off of the accelerator without touching the brakes. There is a service advisory for this (RECALL/CAMPAIGN 15582 UNWANTED BRAKE LIGHT ACTIVATION). As received, both my 2014 and 2015 Spark EVs had a 1.5 second delay. This is dangerous to the driver behind you because unless he is paying attention, he might not notice you are slowing down. Now, when I back off the accelerator so I feel the regenerator drag and I don't touch the brakes, I know the brake lights are turned on. I have checked this at night to make sure.

Thanks so much for the great info. I've been reading through a bunch of Volt threads now and its pretty cool that most people do drive solely in Low. I just wanted to make sure it wasn't harmful to the car by driving at normal speeds and flat ground in Low. I'm sure I'll have to re-wire a lot of thinking with an EV now than what I'm used to!

But to clarify, L does not 'save brakes'.
When you drive Normal Style, (using the brake pedal to slow/stop, and allowing the car to 'coast' when you let off the Go pedal)
When you step on the brake pedal you get regen ONLY up until you max it out, then the Friction Brakes start blending in.

Driving in L - 1 Pedal Style, you have to control the speed constantly. Keep your foot on that pedal the whole trip, except for complete stops, obviously.

Use the power flow display option to see this.

There is no performance difference. It's just whatever you prefer and how efficient you drive. Or not !
It's a fun, cheap EV!!

NORTON said:

But to clarify, L does not 'save brakes'.
When you drive Normal Style, (using the brake pedal to slow/stop, and allowing the car to 'coast' when you let off the Go pedal)
When you step on the brake pedal you get regen ONLY up until you max it out, then the Friction Brakes start blending in.

Driving in L - 1 Pedal Style, you have to control the speed constantly. Keep your foot on that pedal the whole trip, except for complete stops, obviously.

Use the power flow display option to see this.

There is no performance difference. It's just whatever you prefer and how efficient you drive. Or not !
It's a fun, cheap EV!!

Click to expand...

Yep! I still have a lot to learn about this car. I wasn't sure at what point, when driving in D, braking switched from regen to friction brakes. Thanks for the additional info.

BUT.... going downhill in L is a blast. I went from South Lake Tahoe up a 5 mile 6% grade to Echo Summit and then downhill all the way to the bottom of the grade near Folsom, CA. I barely touched the brakes and, when I reached the bottom of the grade, I had almost as much range left as when I left South Lake Tahoe. Regen at its best!

Your comment about constantly controlling the car's speed when driving in L is correct. You have to learn how to do it. I drive with a very soft foot on the accelerator to avoid constantly speeding up and slowing down. I may switch back to driving in D and collect battery use / percent data for a while to compare with the data I already have for driving in L. Given your comments, I would expect there should be little or no difference.

Using L, one has definite control over when the friction brakes are applied. In D with blended braking, the point at which the friction brakes also take part is unknown. One can say "when the brakes are strongly applied", but that's nebulous. From simple experiments, it seems releasing the accelerator pedal in L result in about 1/2 of max regen one can get by pressing hard on the brake pedal. One can infer that to be the case for D as well, though it's far from certain. I wish L would regen harder at max regen power rather than just 1/2.

As I point out in my blog post on regen braking, going down the hill recaptures roughly 75% of energy used to climb the hill (or 85% from Francis' experiment). One must still account for constant speed energy, so you wouldn't get back 75% of the total energy expended, but just the additional energy used to climb the hill.

http://sparkev.blogspot.com/2016/05/regenerative-braking-efficiency.html

SparkevBlogspot said:

Using L, one has definite control over when the friction brakes are applied. In D with blended braking, the point at which the friction brakes also take part is unknown. One can say "when the brakes are strongly applied", but that's nebulous. From simple experiments, it seems releasing the accelerator pedal in L result in about 1/2 of max regen one can get by pressing hard on the brake pedal. One can infer that to be the case for D as well, though it's far from certain. I wish L would regen harder at max regen power rather than just 1/2.

As I point out in my blog post on regen braking, going down the hill recaptures roughly 75% of energy used to climb the hill (or 85% from Francis' experiment). One must still account for constant speed energy, so you wouldn't get back 75% of the total energy expended, but just the additional energy used to climb the hill.

http://sparkev.blogspot.com/2016/05/regenerative-braking-efficiency.html

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I recently realized that regen fed back into the battery may mess up my battery capacity calculations when I use kWh used / % battery used. My wife drives our Spark EVs in D and I drive in L. Perhaps it averages out. I am going to drive in D for a few charge cycles to see if I can see any changes in calculated battery capacity at the 50% usage point as compared with my recent data. Right now I am averaging 18.8 kWh for the 2014 Spark EV and 17.73 kWh for the 2015 Spark EV.

From a driving point of view, I really prefer driving in L as I feel more in control.

PS: you have a great blogspot. I really appreciate all of the useful information and comments I find there for this great little car. Thanks again.

I only drive in L, and make frequent use of cruise control. Coming off cruise control can be annoying with sudden deceleration, but careful planning on throttle (?) makes it ok. Tesla uses strong regen with accelerator (more than L) and brake pedal is only used for friction brakes. For those who plan to get Tesla later, driving in L is a good practice.

Thanks for the compliment about the blog. I write what I'm curious about, and I think other people would have similar questions. Even if we're away, those words will live on to help future generations (100 years from now?) see what a revolutionary EV SparkEV was.

SparkevBlogspot said:

I only drive in L, and make frequent use of cruise control. Coming off cruise control can be annoying with sudden deceleration, but careful planning on throttle (?) makes it ok. Tesla uses strong regen with accelerator (more than L) and brake pedal is only used for friction brakes. For those who plan to get Tesla later, driving in L is a good practice.

Thanks for the compliment about the blog. I write what I'm curious about, and I think other people would have similar questions. Even if we're away, those words will live on to help future generations (100 years from now?) see what a revolutionary EV SparkEV was.

Click to expand...

I often think Chevrolet is making a big mistake by not keeping the Spark EV on sale for about $15-20K in spite of the Bolt EV and I haven't come up with a good reason to abandon my Spark EV for a Bolt.

Does the Torque app work with the Spark to determine regen amount? I'm able to tell when I max out the regen on my Prius plug in by monitoring regen amps. When I press the brake pedal further and no additional amps of regen occur, I have maxed the regen and activated the friction brakes.

Redpoint5 said:

... When I press the brake pedal further and no additional amps of regen occur, I have maxed the regen and activated the friction brakes.

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The Spark EV has a display config that shows kW of power for accel and decel.

I think I see 60kW for max regen.

A simple and cheap test is do a stop, while driving in D, at around 50-55kW of regen. This is a very decent braking rate.
Hop out with a cheapo IR temp reader and point it through the wheels at each of your discs. You may not see any heat which means Zero Friction Brakes !

I have the Torque Pro app, but the OBD to BT adapters I have tried don't talk to the Spark EV's ECM. I gave up trying. It worked great when I had a Volt.

Side Note: I came down Pikes Peak in my Volt riding the brake pedal all the way, just like a dumb tourist. When I stopped at the Ranger Safety Brake Check Station my front discs were 75° on a 65° day. The SUV's brakes in front of me stunk to high heaven. I heard the Ranger tell the driver their brakes were near the limit and they really should park for a while.