(1999-2004) New Edge Mustang V6 & V8 GT Tech

Toxic Colt · #1 11-24-2010, 03:43 PM

Hey Guys as most of you know i just had a set of BBk shortys installed and ive only been driving the car for about a week and out of nowhere the check engine light decided to come on and i hooked it up to my SCT DashScan and my car is throwing the code of P0420 which i looked it up is either due to a dirty O2 Sensor or due to a bad Catalytic Converter, I was just wondering if anyone else that has had a header swap has run into issues like this in the past with their cars? And does anyone know how to tell what the problem actually is?

**Stangman Jonathan** · #2 11-24-2010, 04:03 PM

02 Sensor most likely. I have to swap out the other 3 on janices since her's came back. Just check them out and see.

**MustangSally86** · #3 11-24-2010, 05:30 PM

Yeah my car has the same code coming up and I haven't done a header swap just had the dual's put on with high flow cats. I changed one of the o2 sensors already, gunna change the other three and hopefully that will solve the problem.

Toxic Colt · #4 11-25-2010, 10:24 PM

Thanks for the input.

mnstrstang · #5 11-26-2010, 05:37 PM

i had that pop up when i installed an Xpipe with high flow cats. I used a Snap on scanner to check mine though and it told me exactly which O2 sensor was bad. my predator wouldnt tell me which one.