So I have a bad cat on my 99 dakota. The material is ratteling around in there and it sounds like crap. I am gonna do the exhaust and replace everything including the cat if I can find a good price and I save for it. Right now I cant afford crap.

But to my question: so since the cat material is ratteling and loose I was thinking about just ramming a pipe through it to break as much free as possible, and then shake it out. Well then I was wondering how this would affect the rear o2 sensor? After all the cat is there to burn off the extra gas fumes and crap. So if I jam a pipe in there break it all free it will affect the mixture being read by the o2 sensor. So my question is how will it affect how the truck runs.

Will it A lean out the mix since it is sensing a rich mix since there is no cat

or b do nothing since the cat is shot

c something else

if it will lean out the mix is there an dummy o2 sensor that will trick the computer to thinking the 02 mix is fine?

I have been thinking about this the last week and havn't figures this one out.

 

I've been driving my 03 for 4 months now with no cat or u2 sensor. People have told me that I will get terrible gas mileage this way, however I'm more than pleased with my milage!

 

What is your mileage running on the highway?

 

It doesnt throw errors to your ECU preventing the Emissions/ODB part of inspections?

 

Our inspection where I live is visual so I just slap on the factory cat for a day. As for highway miles I'm getting 20mpg +\-

 

I forgot its simple up there!! lucky bastards...

 

Us western PA folk haha

 

Ha i dont have any inspections! I plan on leaving the carcase of the cat there and just hollowing the damn thing out.

 

if you're going to go with no cat I'd
recommend just eliminating it and putting a pipe there. The exhaust will blow through and kind of whirl around in an empty chamber the size of a cat. For the most free flowing, just get rid of it.

 

Im not gonna hallow the whole thing out, Im thinking of just driving a pipe through it and the outer piece of the converter will remain in there. Air is like a fluid and will take the path of least resistance and will flow down the center.