Smac

Thanks. I have driven it over this past year, with no other problems. It is simply annoying. Thanks for insights and explanations.

I have a higher mileage 250,000 km (155,000 mile) Crosstrek. Owned for one year. Intermittent codes come that suspends Cruise control. At a mechanic shop, they found P0420 and said post converter 02 sensor is crossing over .45 volts steady. ( they say should be at .45) they said no external damage but temp equal across converter therefore internal converter damage. They also suspect cat 02 sensor is seized. They recommend replacing convertor. $2000 Can. ($1500 US). Anyone with insights if this is coherant. any other options? I called local Subaru dealership. They said I could try Cat cleaner (Sea Foam). Independent Mechanic said this will gum up Cat Converter and cause it to fail sooner. any advice?