I have a 2001 Monte Carlo LS with about 117,000 miles on it. After the infamous coolant/oil leak, I repaired the intake manifold gaskets. In the process, I also replaced both O2 sensors and the catalytic converter, as well as the throttle body gasket.
That being said, I am still getting error code P0420. I have noticed that my car is running VERY rich - half a talk of gas gets the car about 100 miles. There are no leaks (no fluid under the car) and no noticeable out of place smells.
Why is my car running so rich, and how can I make it return to normal?
have the same problem?
Thursday, November 8th, 2007 AT 10:27 PM