Three in four Britons don't know how to check the oil in their car, leaving an opportunity for dealers' aftersales marketing teams.

The Mobil1 research also found almost half of drivers don't know why oil is used in engines, and nine in ten were unaware that using the correct oil can boost fuel economy and prolong the life of the engine.

"At a time when British car owners are feeling the pinch like never before, they could be driving blindly towards expensive engine problems in the future," said a spokesman.