Range 17% worse for SL than SV under identical conditions!

[Kaiser]

I own two 2013 LEAFs--an SL and an SV. The SL gets much worse range than the SV (roughly 3.5 miles/kwh vs 4.2 miles/kwh) even though it's driven on the same routes by the same people. The SL's range seems to have become worse over the last few months, but it's hard to tell for certain.

Today I conducted a more scientific test: I reset the efficiency gauges in both LEAFs and then had the SL follow the SV for about ten miles, driving as identically as possible. The route included some flats, some hills, and some highway. The SL performed even worse (3.8 miles/kwh vs 4.6 miles/kwh).

The dealer is stumped. This isn't normal, is it? Is this a trim specific issue, or a problem with the motor or battery?

 

[Boomer23]

I own two 2013 LEAFs--an SL and an SV. The SL gets much worse range than the SV (roughly 3.5 miles/kwh vs 4.2 miles/kwh) even though it's driven on the same routes by the same people. The SL's range seems to have become worse over the last few months, but it's hard to tell for certain.

Today I conducted a more scientific test: I reset the efficiency gauges in both LEAFs and then had the SL follow the SV for about ten miles, driving as identically as possible. The route included some flats, some hills, and some highway. The SL performed even worse (3.8 miles/kwh vs 4.6 miles/kwh).

The dealer is stumped. This isn't normal, is it? Is this a trim specific issue, or a problem with the motor or battery?

Nope, not normal. My 2013 SL has great range and economy. I don't have an SV to compare it with, but some others have both. Perhaps someone else who has both can comment.

 

[cwerdna]

The SL has 17" wheels and tires. That might account for some less efficiency/less range. How about tire pressure on both? Were the HVAC settings identical, preferably off?

Unfortunately, there's no way for you to check alignment w/o having it on an alignment rack/machine.

 

[Kaiser]

HVAC settings were identical.

I didn't check the tire pressure. The test occurred just after dealer service, and the cars were purchased within a month of each other and have similar mileage, but who knows--the pressure could be different in the cars. Still, 17% is a lot to attribute solely to tire pressure or moment of inertia.

 

[cwerdna]

^^^
Tire pressure is super important. Who knows what they're at? Ages ago when I bought an 02 Maxima, I discovered all 4 tires were way overinflated. I think the max sidewall pressure was 35 psi and they were at least 40 psi. Maybe they had been intentionally overinflated somewhere along the long (even at the factory) to avoid flat spots?

 

[DanCar]

I get better range in my SL than coworkers with their S and SVs. Mostly attributed to better driving habits such as slower driving and only braking with B mode. I wonder if alignment is off.

 

[Nubo]

The trailing car could have less efficiency due to not being able to anticipate moves by the other car. To make it more reliable, and account for driver differences, the test should be performed by switching positions AND drivers. You'd need 4 permutations
driver 1 - lead SV, driver 2 - trail SL
driver 1 - trail SV, driver 2, lead SL
driver 1 - lead SL, driver 2 - trail SV
driver 2 - trail SL, driver 2- lead SV

Tire pressure can make a BIG difference if there is under-inflation. Also, alignment. or even something like an under-body panel missing or hanging; creating drag. There are mechanical possibilities, such as dragging brake pads.

It's also possible one of the meters is off. One of the aftermarket displays might give a more accurate gauge of energy per mile.

What are the ages of the cars?

 

[Kaiser]

Both cars were manufactured in March.

2013 LEAFs have a low tire pressure sensor for all four wheels but I don't know when it activates.

Both the instrument panel efficiently meter and the "GPS" efficiency meter agree on the poor numbers.

I'm not going to run all test permutations as there is a clear efficiency difference even in general usage, where all drivers use all cars about equally. Shadowing a car by ten meters in Eco mode doesn't permit much difference in driving styles (in my experience). There are no hanging body panels but I suppose brake pads could be an issue.

An additional wrinkle is that the SL also tends to have worse acceleration than the SV, to the point where it's noticeable by a discerning driver.

 

[RegGuheert]

If you only drove ten miles in your test, then I don't think you can say the range of the SL is different. The difference could be partially or completely due to errors in the gauges.

 

[gbarry42]

If the statement is really true, then you will be able to demonstrate that the "worse" car runs out of juice long before the other. I know we ultimately have to use gauges to determine some things, but we want to minimize this and choose readings we can rely on. The Miles per kW reading has been questioned from time to time. If it were me, I'd try to answer two questions. One, are we really putting all the energy into the battery? The GID meter can tell us this, and so can charge times from empty to full. The other is, how far can I really drive until it says it's empty? The "bars", SOC (if 2013), and GID meter should concur about where "empty" is.

When all is said and done, if one car really goes a lot less distance on the same charge, then it means you are throwing away killowatts of energy somewhere. Time to feel around for something that's a lot hotter than it should be. IR thermometers (and those fancy IR cameras) can help here. It's gotta be going somewhere. 17% isn't peanuts.

The Leaf Spy would be helpful here, as it not only gives you GIDs, but tire pressure and battery temperatures, too. That "not so good acceleration" is going to cause folks to question the battery, and high resistance will show up as heat.

 

[smkettner]

Need to set the pressure same and sidewall max. Climate control should be OFF. Extend the test drive to 50+ miles.
JMHO

 

[stjohnh]

Yep, I vote for efficiency meter being inaccurate. It is a fairly complex calculation based on inaccurate information, specifically how much energy actually flows out of the battery in a specific unit of time. I have a 2013 S and 2013 SV. Meter on the S is clearly different than the SV, yet when both are driven from 100% to Turtle, on the same route, with same driving technique, they get nearly identical range (right at 100 miles).

At the end of the day, no meter readings actually count, ONLY how far you can actually drive.

I doubt the dealer will pay much attention to you unless you actually see how far you can really drive each car, and show they are clearly different.

 

[bowthom]

Check the energy display to see if it shows anything. If the car is drawing excess current (or mistakenly so) it my show there. My 2011 uses about 250W of ancillary power when on and not driving. Hvac off shows zero. An after market device (LEafDD etc) will give you the current draw from the battery, maybe that would tell you something.

I dunno, just throwing out ideas.

 

[LeftieBiker]

^^^
Tire pressure is super important. Who knows what they're at? Ages ago when I bought an 02 Maxima, I discovered all 4 tires were way overinflated. I think the max sidewall pressure was 35 psi and they were at least 40 psi. Maybe they had been intentionally overinflated somewhere along the long (even at the factory) to avoid flat spots?

I wouldn't call 40 psi "way overinflated", just "high inflation pressure." If the sidewall reads 44 psi max as most do, 40 psi is fine. In fact, with the Ecopias it's safer than 35 psi.

 

[Nubo]

An additional wrinkle is that the SL also tends to have worse acceleration than the SV, to the point where it's noticeable by a discerning driver.

Well if you have a safe place for a runoff, that's an easy test since there is no driver skill involved in "launching" a LEAF. 0-40mph should be revealing.

Carrying anything heavy in the SL?

I'm sure someone will know the weight difference between the two package levels....

 

[cwerdna]

^^^
Tire pressure is super important. Who knows what they're at? Ages ago when I bought an 02 Maxima, I discovered all 4 tires were way overinflated. I think the max sidewall pressure was 35 psi and they were at least 40 psi. Maybe they had been intentionally overinflated somewhere along the long (even at the factory) to avoid flat spots?

I wouldn't call 40 psi "way overinflated", just "high inflation pressure." If the sidewall reads 44 psi max as most do, 40 psi is fine. In fact, with the Ecopias it's safer than 35 psi.

The 02 Maxima didn't come w/Ecopias. I don't think they even existed in 2001, when I bought the car. I'm pretty sure the max sidewall pressure on the OEM tires of that car was 35 psi (NOT 44 psi), so to have them inflated to over 40 psi (might've been as high as 45 psi) is overinflated in my book.

I also don't know about "most do". I'm pretty sure the max sidewall pressures on the tires that came w/my 04 350Z was also 35 psi. That was also the recommended door placard pressure.

 

[LeftieBiker]

Sorry, I wasn't clear. I didn't mean that the Maxima came with Ecopias, but that sometimes high inflation pressure is not only not bad, it's actually good. As with the Ecopias on the Leaf and Prius PHEV. If the max pressure is 35 then 40 is bad, but it's been 44 on most tires for quite a few years, now. I remember 38 max...

 

[DaveinOlyWA]

i agree that 10 miles is not enough of a test to make a difference. I drive the same route in THE SAME car with little as far as variance of speed, route, temperature or traffic (the benefits of being on the road frequently at 4 AM or earlier) and see the variance you see.

granted, mine is different days but I also have several days of data (have tracked my performance every day since day one) but have a lot of data tracking first bar loss, first 15 GIDs after a full charge, etc. and found that you really need to do it at least 10-20 times.

also, do a range test. run both to VLB from a full charge. if what you have seen pans out, the difference should be pretty extreme

 

[TickTock]

It may shed some light on the problem if you also took a temperature reading off the four brake rotors after an identical drive (preferably with very little driver initiated braking). Maybe the low-friction brake caliper is misbehaving. Or the parking brake is mis-calibrated. No-touch IR temp gauge would work well for comparative analysis. Maybe try jacking up each wheel and testing for drag. That said, I agree, it is probably the instrumentation. That big a difference represents A LOT of energy going somewhere (~0.5kWh) or, assuming 45mph, ~2.3kW more power (equivalent to having two 1200W, household electric heaters on somewhere in the car) so it won't be able to hide if it is real.

 

[adric22]

My guess is either tire pressure or a wheel alignment issue. That can cause some extra friction as the car moves down the road. You may not notice the car being out of alignment if both wheels are pointed inward or outward in equal amounts.