Error code

[helmsman]

My check engine light came on in my 2002 solara. The code was P0420 Witch means Catalyst efficiency Below threshold (bank 1) What could be causing this? Anything easy to fix? or should I take it in?

[ST185]

Possible causes,
- Catalytic converter might be clogged
- Bad O2 sensor
How is your gas mileage?

[richd978]

do you have a aftermarket exhaust?

[helmsman]

Stock exhaust. Milage is about the same as it has always been. 75,000 miles on it by the way.

[Nad1370]

Take it in.

Cats are warranteed for 8 yr/80,000k miles.

[1st Gen Sol]

I would bring it in to the dealer and get it checked out.

[ST185]

Beware of the dealer that will try to tell you to do the fuel injection cleaner, throttle cleaner, etc ... Those things won't fix the problem.