How can the speed sensor be faulty If the speedo is working propely. ?? I have seen people blame the speed sensor before, but how. ?? Am I missing something. ?? The speed sensor operates the speedo, so surely it either works or it doesn't. ??
We have fitted several speed sensors on focus's, but that has been for the speedo dropping off and cutting out. ( at the same time )
I would fit an Idle speed control valve first as they never seem to work properly after cleaning on most fords and they are common for going faulty. ??
you could check to see if the iac valve is getting switched by the ecu.