The Toyota AD engine family is a series of 16 valve DOHC inline-4 turbo diesel engines with electronic common rail direct injection using an aluminium cylinder head and an aluminium cylinder block with cast iron liners derived from the petrol Toyota AZ engine. The AD engine is offered in 2.0 and 2.2 liter versions. These engines are produced mainly for Europe, but few are exported to other areas such as India or New Zealand.

The Toyota Avensis is a mid-size/large family car built in Derbyshire, United Kingdom by the Japanese automaker Toyota from October 1997 to August 2018. It was the direct successor to the European Carina E and was available as a four-door saloon, five-door liftback and estate.