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1,778 wh/mile reading on my Tesla 3 LR RWD

1,778 wh/mile reading on my Tesla 3 LR RWD

After driving just 100 miles from a 90% charge the battery goes down to 20-25% of range left. After driving 50 miles, 100+ miles will come off my range and I would have to charge it for 4-5 hrs at 23 miles/hr to get it back to 90%. So it does not seem to be a reading error but my Model 3 has actually lost 100+ mile of range.

I drive 12 miles to work and 12 miles back home, less than 25 miles round trip yet I lose 40-50 miles off my range. My commute is local roads going 40-50 mph most of the way. It seems that when my M3 is stopped at a red light for a little while then SLOWLY accelerating to 20-30 mph again there will be a large spike in the reading. There is much less of a spike if i am moving at very low speed 5-10 mph and decide to punch it.

It's not once in awhile but every single time, every single day when I drive my M3 the reading starts at 500+ wh/mile, sometimes 900-1300 and as high as 1,778 wh/mile. After 10 miles into the drive the reading is still averaging 350-400 wh/mile. And no matter how short or long the trip it does not go below 300 hw/mile average.

I am not concern about the high wh/mile in the beginning of the drive, but that it is sustained at 350-500 kw/mile on a 10-20 mile stretch, driving in the most conservative way possible. No launching or punching it. I am concerned that after just 100 miles of conservative driving my 90% battery goes down 20-25%.

I do not use Sentry mode, cabin overheat protect is off, dog mode is off, No third party app. Car is stock nothing added. Brake Regen is On, no excessive braking or acceleration. Car is always parked in my home garage or work parking garage. Do not turn on seat heater or heat. AC now set to 70 degree and 3 when I'm driving. Turning off the AC I get better wh/mile but its not much lower.

I am not even getting 200 mile of range at the rate my M3 LR RWD is consuming energy. Trip Odometer A is around 150 miles at 324 wh/miles and Odometer B is almost 300 miles at 316 wh/miles

jjgunn | 2019年8月22日

Multiple people reporting high unusual usage with firmware 2019.28.3.1

When you go in for service, let them know. In fact, update your service appointment with the information

majassow | 2019年8月22日

Ke = 1/2 mv^2

Silver Surfer | 2019年8月22日

I was having this issue way before the firmware 2019.28.3.1 update

spuzzz123 | 2019年8月23日

Turn off sentry mode, cabin overheat protection. If you use any third party apps, stop. That should minimize your vampire drain. I only lose 1-2 miles parked in garage or overnight.

The spikes in wh/mi you see early in your drives aperfectly normal, as well as the 50 wh/mi spike when you first accelerate. Also like you, I had the higher estimated range (325) then after an ota it started showing about what you show (277 @ 90%.). I don’t worry about it...it’s just an estimate.

But I don’t quite get your 324 wh/mi on an extended 150 mile trip. Unless you were driving over 75 or it was uphill or it was wet roads. That seems high. Would make your range about 230 miles. If you can demonstrate that sustained high wh/mi over time (keep a trip meter / don’t reset it) then you may have a service case.

spuzzz123 | 2019年8月23日

But for sure don’t worry about initial high spikes ... I’ve seen over 2000 in my first minute of drive. It’s absolutely normal. It takes a lot of energy to move a car from zero to 50. And your distance traveled is tiny in that first few seconds. So you have a pretty high numerator and a tiny denominator. Makes for a silly big number. Then once you have momentum, maintaining the speed takes relatively less energy....while you are adding distance to your denominator. Then your usage comes way down.

Devilstower | 2019年8月23日

Yep, I'll join those who have seen 4-digit numbers show up early in a drive. On the other hand, I also looked down about a mile into a drive the other day to see a reading of -87. The readings on a short drive are just wild. Also, I left my car sitting over a week out of town and came back to find it with just 135 miles left -- vampire drain can really suck on a hot day if the comfort setting is on.

On the other hand, it does seem like you're experiencing something that's impacting your range significantly. That's always worth asking the service center to check.

ReD eXiLe ms us | 2019年8月23日

Your car is fine. Do not bother your Service Center.

derotam | 2019年8月23日

Short trips are not a good measure because there can be huge initial energy usages that don't have enough time/distance to get canceled out or otherwise recover from. Specifically you A/C and Heater. You are in Houston in August so I'm pretty sure you aren't using the heater but the A/C has a big energy spike when it starts up the compressor and will be high until the temp starts coming down in the cabin.

Also, check to make sure you Cabin Overheat protection is set for "No A/C" so it doesn't kick on while parked.

Sentry mode uses I think about a mile-ish or so an hour while parked also.

Bighorn | 2019年8月23日

Normal—not close to my record of 8100. Keep studying.

Silver Surfer | 2019年8月23日

I do not use Sentry mode, cabin overheat protect is off, dog mode is off, No third part app. Car is stock nothing added. I don't even charge my phone or any other device in the Tesla. Car is always parked in my home garage or work parking garage. Do not turn on seat heater or heat. AC is set to 68 degree and 5 when I'm driving

I hardly go over 65 mph, 90% of the time I drive local roads going 40-50 mph. I am a very conservative driver and even more cautious with this issue.

I drive 100 miles and its down to around 20-25% battery. Trip Odometer B is almost 300 miles at 316 wh/mile average

hokiegir1 | 2019年8月23日

"It seems that when my M3 is stopped at a red light or traffic then moves again there will be a 50+ wh/mile spike in the reading."

So, stop launching off the line. ;) I know it's fun, but if you are concerned about efficiency, then that's not the way to get it. Try chill mode on this one.

As others have noted, short drives make for a smaller "denominator" (the "per mile" part of watt hours per mile) and the energy needed to get 4000 pounds moving is not insignificant...so shorter trips will be less efficient. It also sounds like our car is relatively new. Many of us noticed a significant improvement after about 2500 miles of use. My average went from 285 wh/m down to 265 wh/m, where it's stayed for the last year.

hokiegir1 | 2019年8月23日

*your -- not our car.

derotam | 2019年8月23日

@Silver Surfer... Great, sounds like there is the answer... Houston, TX in the summer with AC set to 68, and short trips. Adding many stop lights will also compound the AC usage effect.

Also...I don't remember the fan speed level, but I believe there is a point where the power usage jumps up starting at a certain fan speed...don't think it was below 6 though.

LostInTx | 2019年8月23日

You're the customer. You have a concern and you want it addressed. I'm in Houston as well and on a recent visit to the service center on 45, I expressed similar concerns.They were not "bothered" at all and were happily willing to pull info from my car and run tests. In my case, they returned the following:

"We have reviewed your battery data and found the High Voltage battery to be in excellent health. At full charge we can see a range of 301 miles compared to 310 when new. This would be considered normal battery degradation. We can also see that your vehicle rarely discharged below 50%. This can lead to a slight under estimation of range. We would like to assure you that the battery is in good health. Thank you and have a nice day."

So the point isn't whether I was right or wrong to ask for the test. It's my car and if I have a concern, I'll ask for help and avoid forum based diagnosis. I doubt we have any Tesla certified service advisers among us.

Append your service appointment reservation, ask them to take a look, then you'll know where you stand.

ReD eXiLe ms us | 2019年8月23日

And, please feel free to 'feel better' after Tesla Service Technicians have told you the same thing we have. Your car us fine. Be sure to report back with your devastating or encouraging results!

"Have fun storming the castle!" -- Billy Crystal as Miracle Max, 'The Princess Bride' (1987)

Bighorn | 2019年8月23日

Oh FFS, don’t bother an already overworked service center staff. My 8100 Wh was in a 2013 model, so none of the features like Sentry mode to cogitate over. You’re in a hole—stop digging and learn from those with experience.

jebinc | 2019年8月23日

@Silver Surfer - Just a thought, you could have a wheel alignment issue. I've read in the TMC forum that others had this issue and it was determined poor wheel alignment from the factory was the underlying cause. Les Schawb won't charge you a cent if the alignment is within spec, so, other than some time, why not get it checked?

andy.connor.e | 2019年8月23日

@ReD

They will probably return with a temper-tantrum topic created about how service did nothing. Because there was not a problem to fix in the first place.

kevin_rf | 2019年8月23日

Being a Prius driver starting in '02, you should be use to the pinball machine giving you crazy high initial mpg readings at the start of each trip then falling back to normal after you have been driving a bit. The Tesla behaves the same... The Tesla pinball machine just isn't as fancy.

gballant4570 | 2019年8月23日

When your drive is 0.1 miles long, and your car spent 170 wh getting out of the garage and getting moving, your trip meter will show 1700 wh/m.; That does not mean you've spent 1700 wh/m you only spent 170. As you drive, the number drops quickly. However, if your initial drive is uphill or at higher speeds, the number will not drop very quickly.
OP avg wh/m over 300 appears to show that there are a combination of shorter trips, not A lot of regen, perhaps some higher speeds, etc.... going on. I frequently see initial wh/m numbers 1300-1700, but my trip averages this time of year come in more in the 195-210 range, and lifetime is currently 238.

OP, keep your trip meter (not lifetime) showing while you are driving, and drive some different routes, lengths, and speeds. Observe the results. Its very illuminating, and you can apply the results in a way that should improve your wh/m averages. You need to do things like that before reaching the conclusion that there is something wrong with the car. BTW, playing music or charging your phone won't even be a tiny blip in your observations.

jjgunn | 2019年8月23日

Turning off AC really helps increase efficiency.

Just tried it this morning. Pulling about 350 miles range at 100% battery (projected)

gballant4570 | 2019年8月23日

However, while running AC constantly, and leaving it running while I am in the store or restaurant (and in the hospital, unfortunately of late) is resulting in trip wh/m averages of 195-210 in my car this summer.

It is important to note however that some miles can disappear from the estimated number based on SOC that are not reflected in the wh/m, at least in my car. However, as someone who understands how the car works, I do not interpret that number drop as a problem with the car.

andy.connor.e | 2019年8月23日

EPA rated range does not take into account unusually high or low temperatures, excessive braking or acceleration, nor excessive use of climate control. People with these kinds of "problems" have probably never considered how inefficient they are until the car started telling them.

jimglas | 2019年8月23日

when did excessive acceleration become a problem?

andy.connor.e | 2019年8月23日

dont know if it is, but there are increased losses the more power you put to the motor. Whats the significance, i dont have the numbers.

andy.connor.e | 2019年8月23日

Doing a quick calc here, 350V battery pack and 211kW engine yields a minimum of 602A current. Following code the wires would need to be sized to support 753A, which means the minimum wire size they can use from the battery to the motor would be 1000kcmil copper (60ºC), if its a single set of conductors.

Being conservative, lets say its a single conductor from the battery to the motor and its 5ft long.

Doing a quick voltage drop calc, if you were accelerating at 10% of maximum power, you would be drawing ~6.02A, and you would get somewhere in the neighborhood of 0.001V drop over the 5ft run.

If you were accelerating at 100% of maximum power, you would be drawing ~602A, and you would get somewhere in the neighborhood of 0.06V drop over the 5ft run.

So to recap, 10% acceleration yields ~(2.857x10^-4)% loss.
100% acceleration yields ~(1.714x10^-2)% loss.

You do in fact get more losses the more power you put to the motor.

andy.connor.e | 2019年8月23日

This is not taking into account losses within the motor, which you should expect to be much higher.

Earl and Nagin ... | 2019年8月23日

@andy.connor.e,
Electric motor losses will essentially be the "I squared R" losses you observed by the current that you've computed. Remember that that current is what creates the magnetic field that moves the electric motor.

andy.connor.e | 2019年8月23日

Electric motors have their own separate impedance. The losses i calculated were in the ~5ft of wire from the battery to the motor. I'd have to dig into the math much deeper to get that, but its nearing the end of the day and i dont have the attention span as i did earlier.

andy.connor.e | 2019年8月23日

And it would not be simply I^2 x R for the motor since they have reactive power and inductance.

Earl and Nagin ... | 2019年8月23日

@andy,
Yes, but those end up averaging to zero much of the time. There are also some chemistry losses in the battery.
The I^2 R losses in the wiring are generally the largest losses though, even in the battery.
Your initial percentages probably won't change much.
Have fun with the exercise though. My Friday afternoon attention span is too lazy to do it. I'm happy with 1st order approximations :-)

aptwo | 2019年8月23日

Silver Surfer, Is your regenerative braking set to normal?

Silver Surfer | 2019年8月23日

My regenerative brake is on standard/normal

slingshot18 | 2019年8月24日

I don’t know. Some of the things reported are independently normal, but that’s some serious range loss over 100 miles, even with AC. I’m in Southern California with 90-100F weather right now. That’s crazy high consumption for 100 miles. If the OP was only complaining about first mile high usage I wouldn’t have posted. But 100 miles having only 25% left is an issue. Have it checked.

vincelorto | 2019年8月24日

Silver surfer, fox ruined you. Here's hoping Disney and MCU does it right.

shellbitt | 2019年8月26日

rebothard 45 to50max psi is very inportant evey day great range.