just change all my plugs and coils, cus my tt was giving me the p0300 codes, the car still has a bad smell comming from the exhaust, any ideas on what this can be? by the way i had to change all my cols 2 time brand new from the dealer, and when the car is warmed up it starts backfiring.

 

search on here there is a thread about this for sometime now hope this helps

 

Your cat converter is definately toast if it smells like eggs and backfires.

 

a cat system collectsparticles from the exhaust. Asits collection builds up it will burn it off giving the smell of rotten eggs / sulfer. It is normal for all cars to do thisnow and then. It will also trigger the smell on cars that are not driven hardon a regular bassis and then the driver floors it. On going smells could be a bad cat.