Changing Catalytic Converter on A3 1.8T

[robetere]

Hi I have a Audi A3 1.8T 1999, With an AGU engine.

Hi my car is failing the MOT on fast idle on CO. The cat has a blow in it. Kwikfit quoted around £450 to replace it.

I've looked on GSF parts they have one for about £120.

I have access to ramps and tools, I was wondering how hard is it? What do I need to do it? How many Lamda sensors are there? Whats involved with the change? Do I need any pastes? Looking at a picture on http://www.vagcat.com/epc/cat/au/A3/1999/201/50/2398011/ it looks like it just slides in one end and 4 bolts on the other.

[zollaf]

no different to changing any other part of an exhaust really. youll probably have to remove the lambda sensor and refit into the new one. DO NOT use any paste before the cat, as this can damage the cat. you should make sure you get a new sealing ring if fitted, and use that.