Bad MPG resolved IS350 AWD
12-20-14, 12:25 AM
#17
I've had my 3IS 350 AWD for about a month now and the fuel economy has been rather poor to say the least. I always get enjoyment trying to squeeze out ridiculous fuel economy figures in my old cars, but it hasn't been an easy task so far with the new car. My father drives a 2010 RX350 and I can usually manage 11L/100KM (21.4 MPG) per tank without much trouble.
My daily commute right now consists of 90% hwy and 10% city, but I average about 11.5L/100KM (20.5 MPG) per tank. I've had one road trip where one entire tank was driven on the highway, but I could only squeeze out 9.0L/100KM (26.1 MPG). Essentially, I'm nowhere near the 7.7L/100KM (30.5 MPG) that's advertised on the Canadian site. Mind you, all of this was driven in eco mode, where I try to make sure that green "eco" indicator remains on even when I need to accelerate/maintain speed.
I can somewhat live with the 20.5 MPG because the car is so beautiful and smooth, but it's disappointing knowing that if I try to drive even slightly more aggressively or use the Sport+ mode, I'll be driving that figure even further south.
My daily commute right now consists of 90% hwy and 10% city, but I average about 11.5L/100KM (20.5 MPG) per tank. I've had one road trip where one entire tank was driven on the highway, but I could only squeeze out 9.0L/100KM (26.1 MPG). Essentially, I'm nowhere near the 7.7L/100KM (30.5 MPG) that's advertised on the Canadian site. Mind you, all of this was driven in eco mode, where I try to make sure that green "eco" indicator remains on even when I need to accelerate/maintain speed.
I can somewhat live with the 20.5 MPG because the car is so beautiful and smooth, but it's disappointing knowing that if I try to drive even slightly more aggressively or use the Sport+ mode, I'll be driving that figure even further south.
2015: City 12.6 L/100km, Hwy 9.1 L/100km
2014: City 11.0 L/100km, Hwy 7.7 L/100km
12-22-14, 12:45 PM
#18
Driver School Candidate
Join Date: Dec 2014
Location: Ontario
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FWIW, your experience is bang on for highway and even better than rated according to the 2015 Natural Resources Canada rating for the 2015 model year (when the testing methodology was revised). See the 2014 vs 2015 ratings below:
2015: City 12.6 L/100km, Hwy 9.1 L/100km
2014: City 11.0 L/100km, Hwy 7.7 L/100km
2015: City 12.6 L/100km, Hwy 9.1 L/100km
2014: City 11.0 L/100km, Hwy 7.7 L/100km
It's a little crazy how automakers can inflate figures so much, as Lexus Canada is still promoting City 11.0 L/100km, Hwy 7.7 L/100km, which is over 15% off from actual for Hwy figures. Maybe their testing is performed during downhill conditions.
07-30-16, 09:28 PM
#19
Driver School Candidate
Glad to know I'm not alone - just got a brand new 2016 IS350 F-sport and on my first couple of tanks I'm only getting 19-20 mpg, about 60% city/40% highway, with occasional bursts of speed in open space. I was really hoping to get somewhere in between the 19/28 advertised range. Maybe it'll get better as the engine gets broken in? If not, I'm gonna start feeling some serious pain at the pump!
07-31-16, 11:16 AM
#20
Lexus Test Driver
Glad to know I'm not alone - just got a brand new 2016 IS350 F-sport and on my first couple of tanks I'm only getting 19-20 mpg, about 60% city/40% highway, with occasional bursts of speed in open space. I was really hoping to get somewhere in between the 19/28 advertised range. Maybe it'll get better as the engine gets broken in? If not, I'm gonna start feeling some serious pain at the pump!
I manage to get 24 MPG combined when I was around 3K on the ODO. Right now, I am at 5K ODO and manage to achieve 26MPG combined on my current tank of gas.
However, this is all done through ECO MODE, not revving like crazy, and 90% HWY commutes.
**According to the cars computer, ONE full tank of gas gets me roughly 370 Miles.
Last edited by nathantse; 07-31-16 at 11:20 AM.
08-01-16, 12:10 PM
#21
believe it or not, the f sport exhaust helps improve mileage.. yeah i know, wtf right? i've run exhausts on all my cars and obviously you see a 1-2 mpg dip. i was running about 22-24 suburbs/city/highway driving on my RWD. since putting on the f sport exhaust and running with it for about 8-10k miles now, my mileage got better. hitting on average between 24-26 mpgs all around driving, as high as 28 mpgs when i drove around the DMV beltway (highway) for a good 50 miles. i was quite surprised!
08-01-16, 12:39 PM
#22
It's been almost 2yrs later/+20K since my first post (forgot about it) and I still get about 25 mpg. Mind you this is based on:
1) Tractional control is off (my Lexus service advisor recommended this since the car is AWD anyways)
2) Driven mostly in Eco mode (really wish NYC was less congested)
3) 90% highway driving
I'm sure every drivers' results will be different based on their respective driving habits, but the above is what worked for me.
1) Tractional control is off (my Lexus service advisor recommended this since the car is AWD anyways)
2) Driven mostly in Eco mode (really wish NYC was less congested)
3) 90% highway driving
I'm sure every drivers' results will be different based on their respective driving habits, but the above is what worked for me.
Last edited by theoryguy; 08-01-16 at 12:44 PM.
08-01-16, 05:57 PM
#24
08-01-16, 07:04 PM
#25
Yeah you're wrong mainly because your perception of what an irregularity is an extreme which is very different from that TCS system's view to the point of being invasive (there are threads within the CL on this subject as well - cockroach theory perhaps?) . I had almost 2 years to test this out, I'm enjoying better MPG, and my Lexus service advisors recommended doing it. Mind you, this might not be something you may want to do if you have RWD as opposed to AWD if you're the cautious type. Additionally, each person has a unique driving style and/or environment that impacts their respective results.
Last edited by theoryguy; 08-02-16 at 06:58 AM.
08-01-16, 07:48 PM
#26
Lead Lap
Well I hope the mpg gets better, I've had my IS350 F-Sport AWD for a couple weeks now and only got 17 mpg for the tank and that was in Eco mode the entire time and babying it. How is it possible it gets the same mpg as my heavy *** v8 GX? I hope it changes as I get more miles on the car but I am going to try the traction control thing just to see even though it really doesn't make any sense.
08-08-16, 09:52 AM
#27
If you drive more conservatively you will get better fuel economy and if you drive in eco mode and drive conservatively you will get even better fuel economy.
ESP/Traction control CUTS throttle (ie, FUEL) when slip is detected. Assuming you are driving aggressively enough to cause slippage in an AWD car, the ESP program is going to apply BRAKE and CUT FUEL so technically you should get better fuel economy with ESP enabled assuming you were driving crazy enough to be causing slip in an AWD car (thus you would already likely be in the single digits on fuel economy anyways).
Mike
08-08-16, 03:48 PM
#28
Yeah you're wrong mainly because your perception of what an irregularity is an extreme which is very different from that TCS system's view to the point of being invasive (there are threads within the CL on this subject as well - cockroach theory perhaps?) . I had almost 2 years to test this out, I'm enjoying better MPG, and my Lexus service advisors recommended doing it. Mind you, this might not be something you may want to do if you have RWD as opposed to AWD if you're the cautious type. Additionally, each person has a unique driving style and/or environment that impacts their respective results.
08-08-16, 07:42 PM
#29
Again, I had 2 years to test this and you have not, so sorry, but yes way.
08-08-16, 07:47 PM
#30
Traction control off on an AWD car did not make a difference. It just happens to be that he had it off. Correlation does not equal causation. He was driving for a year in Eco mode and trying to see if he was saving on fuel economy. You will unconsciously (and perhaps consciously) drive more economically when doing a mpg experiment. Heck, the first picture (the before picture) he posted shows the car in sport plus mode when he was getting 19mpg. The second picture (the after picture) shows the car in Eco mode. That is telling.
If you drive more conservatively you will get better fuel economy and if you drive in eco mode and drive conservatively you will get even better fuel economy.
ESP/Traction control CUTS throttle (ie, FUEL) when slip is detected. Assuming you are driving aggressively enough to cause slippage in an AWD car, the ESP program is going to apply BRAKE and CUT FUEL so technically you should get better fuel economy with ESP enabled assuming you were driving crazy enough to be causing slip in an AWD car (thus you would already likely be in the single digits on fuel economy anyways).
Mike
If you drive more conservatively you will get better fuel economy and if you drive in eco mode and drive conservatively you will get even better fuel economy.
ESP/Traction control CUTS throttle (ie, FUEL) when slip is detected. Assuming you are driving aggressively enough to cause slippage in an AWD car, the ESP program is going to apply BRAKE and CUT FUEL so technically you should get better fuel economy with ESP enabled assuming you were driving crazy enough to be causing slip in an AWD car (thus you would already likely be in the single digits on fuel economy anyways).
Mike