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Laughable JX35 Gas Mileage

19K views 15 replies 7 participants last post by  John P Meirhofer  
#1 ·
We recently bought a 2013 JX35. It's been a decent car so far, with one big exception: the gas mileage is abysmal.

Our typical daily use involves some neighborhood driving, a little bit of stop and go, and some short highway stretches. We are typically driving on Standard Mode and have yet to have a tank of 93 octane average over 17.4 MPG. Our typical average is in the mid 16's, and the current tank is running around 14. And we're driving this thing like a couple of grandmas! Our ten year old Honda Pilot crushes it in fuel economy, and it's running on 87 octane.

One thing I've noticed is that the CVT so heavily favors the lowest possible gear ratio (around 1,000 to 1,500 RPMs) that the engine is constantly lugging. And when it is lugging like that ,the 'real-time' gas mileage meter hangs in the low teens or single digits. It almost seems that in an effort to be more fuel efficient, the computer is actually making it worse.

Is this normal behavior for this car? Is our engine just really inefficient at these low RPMs? Can the CVT be updated to choose more efficient ratios? Is there something I can take to the dealer to force their hand to do something about it?

Thanks for any tips/tricks/suggestions.
 
Discussion starter · #7 ·
Thanks for all of the responses, guys. With all due respect, I'm an engineer, have owned luxury cars for years, and have driven several cars with CVT. This isn't is a case of my misunderstanding what a CVT is/does and not appreciating luxury. However, it appears that the consensus here is that 14 - 16 MPG is within the normal range for this car for mixed city/highway driving, so I'll just adjust my expectations.
 
Discussion starter · #14 ·
Try driving it in sport mode, where it will simulate the shifts of a normal transmission (i.e., the CVT will use fixed, discrete ratios, vice an infinite one designed for constant engine RPM in it's sweet spot. Consequently, the engine RPM will raise and fall with the "shifts", so the engine won't feel like it is lugging.
That's a good suggestion, Rooster. I have tried that and do like the fact that it chooses gear ratios that are a bit higher and doesn't immediately dive down to 1,200 RPMs and lug like it does around town in Standard and Eco.

The drawback that I've seen is that the pedal becomes so responsive in sport that it becomes a very fine line between "peppy" and "honey, slow down!". I'm not trying to set any speed records. :)

Update on my MPG situation: I finished the last tank at 15.9. So a little more what has been reported as 'typical'.
 
Discussion starter · #15 ·
With 50% city/HWY I get 24.5 on my 2013 model with the older CVT so either your vehicle isn't tuned correctly or your driving it harder than normal. Bring it to the dealer and have them check the engine, filters, etc... to see why it's not breathing/operating normally.
Thanks for the perspective, yeller. I'm pretty sure I'm not driving it harder than average, so I'm hoping the dealer will be able to suggest or fix something.

It's become a quest to see how much I can raise the gas mileage by adjusting my driving style, so I feel like I'm babying it as much as possible. I'm sure it would help a lot if I had more highway time. I'm interested to see how it does on our first road trip.