Hi.My car is a 1993 wrx import.Had my car mapped two weeks ago by Duncan(raceDynamix) and he said that my lambda sensor was faulty.The lambda sensor on a 1993 wrx is on the exhaust manifold and when i fitted some ported headers i moved the sensor to the down pipe before i had it mapped.Had a look at the facelift impreza lambda sensor that goes on the down pipe but the wires are a different colors.Does anyone know how to wire up a facelift lambda sensor to a 1993 wrx pre facelift wiring?

 

The later ones are 4 wire. Early ones 3 wire. You need the early 3 wire type. Genuine recommended. I've heard non genuine don't last too long.