After driving 2000 CRV from Canada to Mexico the check engine light came on. Got a scope reading, the temperature sensor was defective. I had it replaced. Car ran well but was using gas. Usually get 530 km.per tank, down to around 450 or less. Changed fuel, air filters. New spark plugs. Improved slightly but not much. Another scope reading showed no codes. Wasn't carrying very much weight, 2 passengers and a bike on the roof. Not enough to make that much difference. Without a code I'm stuck. Anyone got any idea?