Engine Error Code P0420 and Transmission leak after CV half-shaft replacement
I have a check engine light on...and I went to Autozone to have a diagnostic check.
The code that came up was P0420 (Catalyst efficiency low-bank 1)
They suggested that the probable causes could be:
1. Cataytic convertor defective (failure possibly due to #2, 3 or 4)
2. Engine misfire or running condition
3. large engine leak
4. engine oil leakage into exhaust-valve guide seals, piston rings.
Well this all be said..the engine idles perfect and doesn't burn oil. The head gasket was replaced when I bought it.
So I was wondering what you all thought...hopefully I only need to replace a oxygen sensor and not the catalytic convertor.
Also on another note I recently had my CV joint pull out of my transmission do to a bolt falling out of my control arm....this being said, Big-O Tire had done a alignment on it a few weeks prior to it, so they took care of the repair costs, but now it is leaking transmission fluid...is there a gasket that needs to be replaced when the CV half shaft is installed?
Any help would be great!
