]code for catylatic converter check engine light will not go off on 2005 Subaru Forester

do i need to replace the catylatic converter before i register the car I just bought it from a private party used and the light went on the next day after i got it. The other flashing light is the cruise control witch will not engage when you try to set cruise control

by in Tracy, CA on December 16, 2013
Get Your Car Fixed at a RepairPal Certified Shop.
We certify shops based on expertise, quality work, and verified customer reviews
1 answer 3 comments
ANSWER by , December 16, 2013
What is the code for the convertor?
COMMENT by , December 17, 2013
P0420 I bet! Makes no difference, how many replies do we get anyway?
COMMENT by , December 17, 2013
green jelly will fix it. Advance auto has it ....$6.99 per 8oz. jug
COMMENT by , December 17, 2013
Shine is cheaper than that! It will fix anything, for awhile!