hi , i'm having trouble cold starting my a3 1.8t agu and have changed my coolant temerature sonsor (blue square 4 pin plug ) however i have noticed another sensor (2 pin rectangular plug )just forward (closer to the radiator) in a plastic junction pipe in the cooling system .
so have i got another coolant temp sensor ? i know some cars have one for the temp guage and one for the ecu , is this the case with my A3 ?

baz