I've had my van for about a month and I've been averaging 18 to 22 miles per gallon except for the one day that I took a big road trip I got up to 24 mpg.
Here's why everyone's gas mileage is much lower than advertised for Nissan nv200s. There's a torque converter that steals your RPMs to give you more torque. The faster you accelerate, the more RPMs are put into tour instead of turning the wheels directly like every other vehicle. I think you have to keep your RPMs slow when accelerating or they just get converted to torque and you waste RPMs and therefore waste gas.
https://www.dnr.louisiana.gov/assets/TAD/education/ECEP/auto/f/f.htm#:~:text=Mpg will be significantly reduced,type of torque converter failure
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