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36K views 32 replies 24 participants last post by  tommy_a_d 
#1 ·
I average is 17.5 l per 100 Kms with about 420 Kms per tank. This seems absurd after 2500 Kms but dealer thinks it is normal. Really... This is rediculous what happened to the 11 and a half city quoted. Dealer also suggested te engine needs to brake in at 12000 Kms!
 
#3 ·
I'm at 12000km an average 13.8 per 100 km, probably about 450km per tank. I have to be pretty lite on the gas to get 13.8. Was getting 14.2, getting better mileage as the car breaks in alittle more. Would be happy with 500km per tank. This is 50/50 highway and city driving lots of hills.
 
#7 ·
I'm at 6,500 km and have averaged 11.5 l/100km. City (which is quite hilly) is about 12.5. My best on the highway is about 9.5 thus far. I've noticed that where I fill up seems to make a difference in mileage. If you're getting poor mileage, switch brands. I haven't driven enough yet following the re-program to see if the mileage has improved or not.
 
#12 ·
McPhee, Which brands have you had the most success with?

After my first tank on the JX, we are getting 19L/100km which is pretty bad - mostly city and rush hour traffic. Having said that, my Audi with a higher output engine gets SIGNIFICANTLY better gas mileage even though the EPA numbers are similar. I also drive the Audi a lot harder.

I think the 3.5L VQ engine just isn't very efficient. We had mediocre mileage on our EX35 too.
 
#8 ·
Ok -some more data on highway mileage post re-program. We did some highway driving this week-end and I hit a new best of 8.2 l/100 km on the destination leg of the trip. I filled up on the return drive with a different brand of gasoline and averaged 10.2 l/100 km. Same highway, cruise crontrol on both trips, so I expected similar mileage.

Both gasolines were 91-octane with the return trip gas claiming to contain no ethanol; not sure about the ethanol content on the destination fuel. The only other factor which could possibly help explain the difference in fuel economy is the elevation change - elevation declined about 2.8 m per 100 km on the destination leg and rose 2.8 m on the return leg. Elevation changes consisted of rolling hills rather than steep inclines. I'm not sure the change in elevation was that material, so am inclined to think the majority of the loss in fuel economy must be the fuel. What's the experience of other JX owners?
 
#14 · (Edited)
MacPhee - thanks for the feedback. Do you typically fillup with regular or premium? On our EX, I noticed better fuel economy with premium (probably because less ethanol in general) but the fuel economy wasn't better by much (i.e. not worth the cost difference).

I'm guessing the first tank from the dealership was 87 octane.
 
#15 ·
The Mallfinder is my wife's car, she drives it about 1.5 miles to work at 30mph. Yeah, she could ride her bike or walk, but there are no sidewalks and she has a roller-crate full of student's papers she has to bring home every night... Anyway, in the winter cold, short hopping, where the motor never really warms up so the ECM is running in "open loop" mode instead of "closed loop" where it's optimizing from O2 sensing and such, she gets 18mpg. When I drive it to work, 28 miles of which 25 are freeway, I get a whopping 28. There is a huge range in mileage depending on your useage
 
#16 ·
Driven a little over 3,000 miles so far. Averaging 18.8mpg on mid-grade premium 89 octane....Mostly from Quiktrip. Short trips mainly on the weekends in city traffic and 18 mile commute on expressway in mixed traffic...And I have an AWD.
 
#17 ·
Shiny - We fill up with premium 91-octane - haven't tried 87 or 89 octane.

I agree with the post from Gibbons that how you drive greatly impacts mileage. When my wife lets the car warm up for 5-10 mins in cold weather before driving the kids 1.5-blocks to the bus-stop, yes mileage is pretty poor. Climbing hills and driving in cold weather also negatively impact fuel economy - as we all know.

As best I can tell, I think the JX is capable of attaining the posted fuel economy ratings. With 10,000 km, winter tires, ski rack on top, and cold weather, I'm averaging 1 l/100 km above the posted ratings. In the spring, once the weather warms up and I swap out the tires, I wouldn't be surprised if I'm able to reach the fuel economy ratings posted by Infiniti.
 
#18 ·
A little info I've learnt from reading is if you want the best bang for your buck gas for performance and fuel economy stick with gasoline that doesn't have ethanol. Most gas stations Esso and Petro Canada have ethanol. I believe Shell is ethanol free for their 91 octane. It should say at the pump. I definitely wouldn't go over 10% ethanol either.
 
#20 ·
cfrp - the reading I've done says you are right (Shell-91 has no ethanol, and non-ethanol fuel should provide better mileage), however I'm finding my actual fuel economy is better with Esso or Petro-Canada vs Shell. It seems totally backward. Perhaps the JX is tuned to accomodate some ethanol in the gas? Does anybody else have some data points on fuel economy in the JX - ethanol vs no ethanol?
 
#21 ·
When I took the delivery of the car from the dealer, I got a full tank of gas and the car showed 460 miles to empty. I drove close to 415 miles before I filled up the tank again at BP with silver grade. This time, I got 375 miles to empty and I drove around 360 miles. I got an average mileage of 17.5 miles with mixed driving of highway and city. Last week, I noticed that the price of premium gas (92 Octane) in Costco was equivalent to the silver grade in BP. One would have expected a better mileage, but to my shock, I got a worst mileage of 280 miles for a fullt ank. I again filled at Costo today and to my surprise, the JX showed 380 miles to empty. I'm not sure how to read this. Is this because the engine is trying to set itself and that's how the computer is adjusting the mileage accordingly?
 
#22 ·
Im not sure what mode you all are using but im 735 miles and 3 months into the new JX35 and i can't even break 16mpg? I have confirmed with another person in service (both waiting for oil change) this car just plain guzzles gas. Anyone care to share how they are doing 19+mpg? btw i have tried mid and super grade fuels and i have the touring package with the 20" wheels.
 
#23 ·
As I mentioned in my last posting, I'm not getting around 19.0 mpg in mixed driving and am betting it is because of the winter fuel blend. I noticed last year with our 2010 Armada and 2001 Mercedes M Class, that both dropped in mpg in the winter but improved in spring when the fuel blend changed.

When I drive, I don't have a heavy foot and tend to use the manual shift mode when I get on the freeway, bumping it to M6. I use the Standard mode almost all the time. I'm usually not in heavy traffic since we live in a rural area, but do have quite a few stop lights and traffic. My best milage was 24.1 on a long freeway trip, and worst was the first tank, which I'm guessing was around 13.0, which may not have been accurate. For the most part, I'm averaging 22.2 according to the on board computer. I do also use the AC all the time and since I didn't notice much of a difference during the long trip we took.
 
#24 ·
Fuel Economy Stats from my vehicle.

Combined is "21.something". I had gotten up to 30MPG with Shell gas at a constant 65mph. At a constant 70mph and I'm getting 27-28MPG. City is similar to 18MPG

The sticker says:
EPA MPG Rating (City/Highway Combined): 18/23/20

So I think our JX is doing better than the sticker rating.
 
#25 ·
There are a lot of things you and me can do to make genuine fuel economy improvements right now. In a lightweight car every item you add decreases your mileage. Driving like a Boy-Racer by aggressively accelerating or breaking not only makes you look like a bit of a fool, but it wastes fuel too. Some of us have a love-hate relationship with the gear stick, but the fact of the matter is that correct use of gears can make huge savings on your fuel bill of up to 15%. Make sure you check your tyre pressures reguarly (at least once every 2 weeks). An under-inflated tyre can increase fuel consumption by 3%, and it will wear out quicker too. Air Conditioning is great in the hot summer months, but only use it when you really need to and just use the blowers the rest of the time.
 
#26 ·
First fill up: 15.56 mpg

Second fill up: 18.02 mpg

Switched to ECO mode after second fill up.

Third fill up: 20.56


These rates are based on my own calculations. This is for city only driving not exceeding 40 mph. I will not take my JX 35 on the open road until later this month.

Traded a Town and Country van and although I miss the roominess of the van, I really love this crossover.
 
#30 · (Edited)
I got my JX at the end of April last year. Since then I put more than 26000 km and it averages around 13 L per 100km. During last summer and now after winter time it is around 12.8 L/100km. I'm putting mostly regular gas in it, and occasionally I used premium gas. Since I didn't see any differences in fuel economy or performance I stopped vasting the money. I tested all modes, eco, standard and sport mode, surprisingly I found out that the best fuel economy is in the sport mode. That was 6 months ago and since then I'm using the sport mode constantly, except during snowing or freezing weather. I'm sure that fuel economy could be better because I drive aggressively.
 
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