hi there I got a code p0420 I changed the upstream oxy sensor. 250 miles later the same code came back..

befor I take it to a shop is there anything I can to to clean out the cat converter, do they sell anything at autozone or advance auto parts...

also when I take it to a shop can they test a cat converter befor I think I need a new one

 

anyone know the best brand name to buy for a catilac converter

for a 2001 dodge neon 5 speed manuel

need part number and brand name

 

I don't know of any way to clean a cat converter. Before suspecting the cat you should clean or replace the downstream O2 sensor. That's the one that measures catalyst efficiency.