Wild swings in the range remaining

[campfamily]

I know there have been a lot of discussions about the unreliability of the range remaining gauge, or GOM, in our FFE, but wanted to share something that happened to me yesterday that I'd never seen before. First, I've had my FFE since May, and currently have a bit over 7,000 miles on it. I was driving on the freeway about 75 mph, and had 17 miles remaining (was about 16 miles from home, which was getting my wife a bit concerned!!). As it often does here in Los Angeles, traffic stopped, and soon I was creeping along at about 5 mph. Within two miles, my range remaining had swelled to 75 miles. Then, as speeds varied from near stop to 20 mph, the GOM showed numbers that varied from 25 to 75, sometimes changing in chunks of 10 miles in a single second. Now, I've seen real-time variations in this display, but nothing as radical as this. Anybody else seen something like this? By the way, when I got home the display showed 8 miles remaining; total journey was a bit over 65 miles.

Background, temperature was about 60 degrees (chilly for us out here!), I had three people in the car, and Air Force had just beat Army in football (we were returning from a gathering of Air Force Academy and West Point cadet families having just watched the game).

Keith

 

[jmueller065]

... as speeds varied from near stop to 20 mph, the GOM showed numbers that varied from 25 to 75, sometimes changing in chunks of 10 miles in a single second. Now, I've seen real-time variations in this display, but nothing as radical as this. Anybody else seen something like this? By the way, when I got home the display showed 8 miles remaining; total journey was a bit over 65 miles.

Oh yeah all the time, this is exactly why its called the GOM! LOL

If you drive 5 mph long enough you'll see 100+ miles....

I've been on a few drives where I arrived home with more miles on the GOM than when I left!

 

[campfamily]

Yes, I have seen variations while driving all the time, just nothing quite as extreme as yesterday.

 

[WattsUp]

... as speeds varied from near stop to 20 mph, the GOM showed numbers that varied from 25 to 75, sometimes changing in chunks of 10 miles in a single second. Now, I've seen real-time variations in this display, but nothing as radical as this. Anybody else seen something like this? By the way, when I got home the display showed 8 miles remaining; total journey was a bit over 65 miles.

Oh yeah all the time, this is exactly why its called the GOM! LOL

Really? I've never seen anything like CampFamily is describing... large, quick swings in the estimate over extremely short periods of time. It usually takes a bit of sustained driving (for at least several, if not tens of minutes) at a particular consumption rate (low or high) for the GOM to be wildly affected.

CampFamily, what were doing before the wild swings? Were you driving in some really unusal manner?

 

[campfamily]

... as speeds varied from near stop to 20 mph, the GOM showed numbers that varied from 25 to 75, sometimes changing in chunks of 10 miles in a single second. Now, I've seen real-time variations in this display, but nothing as radical as this. Anybody else seen something like this? By the way, when I got home the display showed 8 miles remaining; total journey was a bit over 65 miles.

Oh yeah all the time, this is exactly why its called the GOM! LOL

Really? I've never seen anything like CampFamily is describing... large, quick swings in the estimate over extremely short periods of time. It usually takes a bit of sustained driving (for at least several, if not tens of minutes) at a particular consumption rate (low or high) for the GOM to be wildly affected.

CampFamily, what were doing before the wild swings? Were you driving in some really unusal manner?

Nope. Just driving down the freeway at 75-80 mph, which is what I do frequently. Had been driving this way for about 10 miles. Then, traffic stopped, and for the next 3 or 4 miles, it was stop and go. This was when I saw the huge variations. Then, when traffic opened up again, and we began moving again, the remaining range settled back down. This was the first time I had seen this type of wild swing in the display.

Keith

 

[hybridbear]

I haven't seen such wild swings, but I've never driven in conditions like Keith. I don't think our FFE has ever even hit 70 MPH...freeways around here don't have speed limits higher than 65 MPH maximum. And we also don't usually have such long stretches of stop & go traffic.

 

[michael]

I've seen wild swings when the battery was really low. As, for example, 80 mile range with 3% battery remaining. Over the next mile it dropped to zero mile range and gave me SSN.

 

[damania]

Nope. Just driving down the freeway at 75-80 mph, which is what I do frequently. Had been driving this way for about 10 miles. Then, traffic stopped, and for the next 3 or 4 miles, it was stop and go. This was when I saw the huge variations. Then, when traffic opened up again, and we began moving again, the remaining range settled back down. This was the first time I had seen this type of wild swing in the display.
Keith

There is a big difference between going 70-80mph and stop and go. You'll get a range difference of 2x between the too and that will a pretty accurate description too. For example, if I drove at 80mph I would have a range of close to 50 miles, but if I drove around 0-30 mph then I would have a range of 100miles. And yes, these are real miles that I can use.

 

[campfamily]

Nope. Just driving down the freeway at 75-80 mph, which is what I do frequently. Had been driving this way for about 10 miles. Then, traffic stopped, and for the next 3 or 4 miles, it was stop and go. This was when I saw the huge variations. Then, when traffic opened up again, and we began moving again, the remaining range settled back down. This was the first time I had seen this type of wild swing in the display.
Keith

There is a big difference between going 70-80mph and stop and go. You'll get a range difference of 2x between the too and that will a pretty accurate description too. For example, if I drove at 80mph I would have a range of close to 50 miles, but if I drove around 0-30 mph then I would have a range of 100miles. And yes, these are real miles that I can use.

Agreed, and I see variations on the GOM when this occurs. However, I had never seen such a dramatic variation, where in the space of 2 miles, my range remaining went from 16 to 75, and then I kept seeing huge variations (10 miles or more) every few seconds. Once traffic broke up and I got moving again, the variations settled down. BTW, my energy useage stayed pretty constant, at about 240 Whr/mile.

One other factor that I just realized I neglected to mention. Right before traffic stopped, while I was going 75 or 80 mph, I was going uphill. That was why I wasn't concerned that I had 16 miles remaining, but the NAV system showed home was 17 miles away; I knew that I'd pick up a few miles once I reached the top of the hill. Traffic stopped right at the top of the hill, and so the stop and go was all flat or slightly downhill. I'm sure that also played a part in the variations that I saw.

Keith

Keith

 

[damania]

I've noticed the meter changes every few hundred feet. It can add or remove 10-20 miles just based on even a 1/2 mile.

I even notice the action on regen. If I braked and my front wheels slipped 5 mins ago, the regen would be weaker on subsequent stops.

Btw, the regen completely SUCKS on the car. I have slipped my front tires on slowing down on almost all my last 10 trips around town. The computer does not keep up and fix the front tires from slipping. All I need to do is slow down before a turn and there's excessive regen on the front tires and traction control completely fails for many many yards. I've figured out that not stepping on the brakes at all while turning, I can turn without any tire noise. If I step on the brake even a little bit, the front tires slip. But not stepping on the brakes on a turn is dangerous cause I don't know what's around the corner including pedestrians.

All electric cars need a motor on both axles for braking. Period. Can't make a good electric car without 2 motors. I don't want to hear anymore.

 

[scottt]

I've noticed the meter changes every few hundred feet. It can add or remove 10-20 miles just based on even a 1/2 mile.

I even notice the action on regen. If I braked and my front wheels slipped 5 mins ago, the regen would be weaker on subsequent stops.

Btw, the regen completely SUCKS on the car. I have slipped my front tires on slowing down on almost all my last 10 trips around town. The computer does not keep up and fix the front tires from slipping. All I need to do is slow down before a turn and there's excessive regen on the front tires and traction control completely fails for many many yards. I've figured out that not stepping on the brakes at all while turning, I can turn without any tire noise. If I step on the brake even a little bit, the front tires slip. But not stepping on the brakes on a turn is dangerous cause I don't know what's around the corner including pedestrians.

All electric cars need a motor on both axles for braking. Period. Can't make a good electric car without 2 motors. I don't want to hear anymore.

You may have an issue with your car. I've always been an aggressive brake-r. Been trying to behave since I got the FFE. I've only experienced the "bunny hop" (what I call it) 3 times. All were braking going down a hill on rough pavement.

 

[damania]

Mine's a 2014. Does anyone else experience front wheel skidding?

 

[jmueller065]

Mine's a 2014. Does anyone else experience front wheel skidding?

Only on really rough pavement (e.g. Michigan roads) or wintery/slippery conditions.

 

[triangles]

Mine's a 2014. Does anyone else experience front wheel skidding?

Mine is a '14 as well. What you describe above does not sound normal at all. I did notice shortly after I got my car that there is a bump in the road right where I'm at maximum braking before a turn in my commute. And I get what could be perceived as the front wheel skidding. I believe what is happening is that the traction control misinterprets the bump as a loss of traction. Since I am at near max regen braking (no physical braking) the traction control cuts the regen instantly and the wheel freewheels for a moment until the physical brakes kick in. This really scared me at first until I figured out it was the bump doing something screwy with the brakes/traction control. I could see if this happened to me and I mashed on the brake pedal the perceived skid could quickly become a real skid. Are you sure your perceived skid isn't the same thing I experienced? I may have to try that same bump with traction control turned off and see if it's any different.

 

[campfamily]

Mine's a 2014. Does anyone else experience front wheel skidding?

Mine is a '14 as well. What you describe above does not sound normal at all. I did notice shortly after I got my car that there is a bump in the road right where I'm at maximum braking before a turn in my commute. And I get what could be perceived as the front wheel skidding. I believe what is happening is that the traction control misinterprets the bump as a loss of traction. Since I am at near max regen braking (no physical braking) the traction control cuts the regen instantly and the wheel freewheels for a moment until the physical brakes kick in. This really scared me at first until I figured out it was the bump doing something screwy with the brakes/traction control. I could see if this happened to me and I mashed on the brake pedal the perceived skid could quickly become a real skid. Are you sure your perceived skid isn't the same thing I experienced? I may have to try that same bump with traction control turned off and see if it's any different.

Wow. Talk about a thread hi-jack. We went from range remaining to front brakes skidding in a matter of minutes.

 

[damania]

Mine's a 2014. Does anyone else experience front wheel skidding?

Mine is a '14 as well. What you describe above does not sound normal at all. I did notice shortly after I got my car that there is a bump in the road right where I'm at maximum braking before a turn in my commute. And I get what could be perceived as the front wheel skidding. I believe what is happening is that the traction control misinterprets the bump as a loss of traction. Since I am at near max regen braking (no physical braking) the traction control cuts the regen instantly and the wheel freewheels for a moment until the physical brakes kick in. This really scared me at first until I figured out it was the bump doing something screwy with the brakes/traction control. I could see if this happened to me and I mashed on the brake pedal the perceived skid could quickly become a real skid. Are you sure your perceived skid isn't the same thing I experienced? I may have to try that same bump with traction control turned off and see if it's any different.

It sounds like a full skid that I go thru. Anyways it lasts for 2-3 seconds and at least 15 feet. The only way I get rid of it is by letting go of the brake. How long does yours make noise?