Replace the ECT and thermostat as a combination. This is very very common. Go to VW and request a new ECT. They will hand you a new sensor that has a GREEN top. If it isn't green, ask for the new superseeded ECT that is green. The one installed on your car is all black, VW has re-designed their ECT's because they are prone to failure.
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Thursday, November 17th, 2011 AT 11:50 PM