My 2015 Lexus RX350 gets very poor mileage that changes with air temperature. The lower the temperature, the worse the mileage. The range goes from about 10 mpg to 16 mpg.
I bought the pre-owned car in 2018 with 32000 miles on the odometer. The gas mileage initially ranged from 18 to 21 mpg. The gas mileage began to deteriorate about 1 year ago.
The engine light is not on.
Any ideas about what the problem may be?