Slicendice1

I have a Lexus is 300h, 2017. I have had it about 2 years, and it has around 48,000 miles on the clock. In summer when temps over 22-23 degrees usually gives 43-48 mpg (UK gallon) urban driving. Motorway 55+ Winter (minus degrees to 10 ish) I get 32-35. This has been pretty consistent until this month when my summer readings dropped to 35mpg about 10 less than it should be which is worrying (and temps are 30+ 25+ 22+ etc). I usually drive in sports mode too. I drive using good hybrid braking 😉 and don't race around too much s- my style has not changed recently so suspecting dirt build up in the fuel systems or air filter perhaps.