Po430 catalyst efficiency below threshold (bank 2)

[Markus Escamilla]

A few months ago i had a random misfire and a cylinder 3 misfire ...I replaced all of that and there was no code being thrown for a few weeks. Now i have p0430. My exhaust pipe on the passenger side smell almost like eggs while the other one smells normal. Could this be an o2 sensor or is it most likely the catalytic conveter

[CamGTP]

Smelling like rotten eggs is the go to sign that the cat converter itself has failed and is no longer working properly.

[Markus Escamilla]

4 hours ago, CamGTP said:

Smelling like rotten eggs is the go to sign that the cat converter itself has failed and is no longer working properly.

Another source told me that if the sensor was bad it could be sending the computer the wrong amount of 02 in the exhaust causing that bank to have too much fuel making the egg smell as well...is that possible or no

[CamGTP]

Yes that is possible but you'd be showing a code for a too rich condition from the sensor in front of the cat converter.

 

If you aren't getting a rich code on that bank, I doubt that is the problem. You can hook up a scanner to the truck and what the front o2 sensors too. Look at the swing in voltage and see what the fuel trims are doing. Normal switching is between .050mv and ~.900mv. Fuel trims roughly within 5-10% of zero all the time. If it was way rich on one bank the trims would be -15-20% as it's trying to pull away fuel.

[Brian Lindsey]

you could take a laser heat sensor gun, and check in front and in back of cat converter , see what your temps are