I drive and a owned a VW tiguan tdi 140 bhp since 2008 ,37,000 miles on the clock ,i am a sunday driver ,but every so often worning lights come on in my car ,just now there is a yellow light the shape of a engine is on ,also when switching of the engine it does not switch of smoothly it judders ,it is a terrific car for the scottish damp and cold weather but i get fed up with these faults,can you advise on what next