i have a p0420 followed by p0172 c0de

Question

i have a p0420 code on my chevy s10 then a p0172 code next

Answer 1

Hi there,

Actually the P0172 code can cause the P0420 code. The first code is rich mixture code. This can be due to a leaking fuel injector or dirty air filter. Once that code is resolved, then the second code for a bad converter might be resolved.