P0420 Pontiac -

Question

Ive got a p0420 code and before mehanics tell me i need a bunch of other things where should i start? It doesnt smoke. Sometimes it acts like it has a misfire and dies could it be back pressure from the catalytic converter?

Answer 1

HI there,

You can get misfiring and stalling from a bad converter, it can also cause a lack of power. Not knowing what all the car needs, I suggest starting with anything that could cause the misfire. If you have a cylinder misfire, then it will put raw fuel into the converter and give you the converter code