Manager Forum

Ok. I have this 2012 Dodge Charger with a 3.6L engine and an auto trans. Mileage at 65,000 miles. Issue is it fails emissions inspection due to a PO420 code. New converter and oxygen sensors do not correct the problem. What now? We have used all OEM parts from MOPAR. As soon as I start driving the PO420 code comes back in less than 5 miles down the road. What am I missing?

Small exhaust leaks near the second o2 can cause this.

Were they replaced just for the code or was the cat really inefficient. Id look for vacuum or exh leaks.

I also found a TSB for that. It requires a reflash. See 21-007-12 for more info.

Ok. Here is an update. Since Chrysler extended the emissions warranty on some vehicles, this one was under warranty so the customer had the dealer replace the converter. When we got the car back, we figured both converters had been replaced. However, since DTC P0420 is a bank one issue, they replaced only the one converter. There is where the problem is. Bank one is the passenger side of the engine and they replaced the drivers side converter. So, consequently, when I got it back,nothing had changed. I only discovered the wrong converter when I looked under the vehicle in my frustration. So. I contacted the customer, he in turn called the dealer and then I needed to explain to the service advisor what the problem was. Once he realized it was their mistake and they had in fact replaced the wrong converter, he admitted they will have a problem with the warranty paperwork. I assured him it was not my problem. The right side converter got replaced and all is ok now. What a deal!

Bottom line. Second guess anything that may have gotten done or said was done.