[mongongo]

First time to dealer they reset, and ran test said all was good, fluke? Rust in exhaust from truck sitting on lot for one year? But now it has happened again one week later. I have no CC codes Only the po420. The key trick does indeed work on 2005's to pull codes.

What am I doing wrong? is it my slow 45 mph home from work driving? is it my 10% ethanol gas? Or is there some trick my dealer needs to know about to put a end to this? Visions of my 150,000 mile blue oval that never did this to me are dancing in my head at night as I sleep. Just kidding, this dodge is the truck of my dreams.. but that engine light has to go!

 

[HappyHour]

That is just odd. What mods do you have. I get that, and so do many others, but it is due to high flow cats. Maybe the gas you are using is tripping it. I just live with mine now. If my CEL isn't on I get worried! LOL

P0420 Catalyst System Efficiency Below Threshold (Bank 1)

 

[mongongo]

No mods at all. I just hope there is not something else wrong besides a "Bad" O2 Sensor. I never have liked the fact that when the O2 sensor sets off the engine light they always say its bad??? It could be doing its job of indicating something else up stream?

 

[slvrmagnum]

It is either a bad O2 sensor or a bad cat... I would tend to lean towards the O2 sensor. All the rear O2 sensors is monitor the efficency of the cats, nothing more. I am one who has high flow cats and I did a mechanical sim to stop the code from popping on either bank.

 

[mongongo]

I hope, Im having a hard time with the cat thing since it only has 1600 miles on it.. It had 19 miles on it when I bought it on aug 22nd of 2006. I hope the year it sat on the lot has nothing to do with this..

 

[faze3]

If it is a bad cat, that's good. There's a federal warrenty of 8/80 on them. The dealership has to replace it free of charge. Even if they reduced the mileage coverage, at 16k you'll be covered. It'll cost them upwards of $300 IIRC. I had mine replaced on a '96 1500.

The warrenty info should be in the owner's manual.

You never know if its bad, even with this low a mileage. Replace the o2 sensor(s) and see what happens?

 

[mongongo]

Dealer called they are gonna replace rear 02 sensor and reflash. I hope it works. thanks for the input guys. This is really to bad for a truck with only 1,600 miles.