I've been told that the Catalytic converter on my Audi A4 Avant (1999)
1.8 Auto has failed because of the temperature sensor failing. The cat
failure must be bad, becuse the engine will only get the car to 30-40
MPH! I'm not convinced that it is the cat.
I was always told that the engine management system had a seperate
engine temp monitor. The sensor that has failed is the sensor for the
temp gauge on the instrument panel.
I've been told that because of the sensor failure, the engine has been
running permanently rich, which in turn has killed the cat.
Does this make sense?