Hello,
I have a P0420 trouble code, that says "Catalyst Efficiency Below Threshold". Can any one give me an idea on how to raise the efficiency of the catalyst? My car is a '99 2.5L Legacy Outback wagon w/ 113K miles. Is this trying to tell me I need to replace the catalytic converter on the exhaust system? Sounds like it going to hurt my wallet. I've searched past posting and didn't find anything. Anny and all help is appreciated.
Thanks
-Nick