rough idle and trouble code

[Brennan]

My car is Idleing very rough almost like it is miss firing. It jumps anywhere from 500 to 1500 RPMs. Also it smells real bad "not sure what the smell is" My check engine light is not on but I do have a trouble code. P0147 O2 sensor Heater Circuit Malfunction (Bank 1 Sensor 3) Could an O2 sensor be causing this to happen.

[RallyRed 98]

bad O2 sensor or the cat itself...

[FlyBoy9994]

Clogged cat for sure.. I don't think a bad 02 sensor would give off a foul odor would it??

Smell is caused by the failure of the honeycomb structure inside the cat and emitting sulfur compounds as a result. The "catalyst" structure inside the cat is breaking up into pieces and clogging whtever good parts of the cat are left. Bad stuff for sure..

Easy fix though!! Remove cat, use a broomstick to clean out a big hole right through the center and replace cat.. also known as the "broomstick mod" Should get rid of the smell and be good for a few extra horsepower as an added bonus...