Question

I got the engine code P0420 on my 2002 Toyota Sienna, what can I do to repair it?

Answer 1

HI there,

The code is for the catalyst efficiency below threshold. This usually means the catalytic converter is no longer doing it's job. Most of the time replacing the converter is the required repair. You can sometimes get this code if you have a faulty rear O2 sensor, exhaust leak or a poorly running engine as well.

Answer 2

P0420 TOYOTA Code - Catalyst System Efficiency Below Threshold Bank 1
Read more: https://www.autocodes.com/p0420_toyota.html