These codes, P0420 and P0430, i.E. Both catalyst converters in the system show efficiency below threshold, showed up today.
The engine is running normally. The only insoluble problem I've had, which has gone on for more than a year, is that a small cloud of black smoke occurs when first starting the engine when its cold, then right away the exhaust is clean. The engine burns very little oil between changes, i.E. I never have to add oil. Other than regular oil and air filter changes, the engine has had very little done to it: about five years ago, I replaced the upstream and downstream O2 sensors on the right bank catalyst only. The spark plugs were replaced about 70,000 miles ago.
I'm wondering how to proceed. It seems odd that both catalytic converters would fail, if that's what's happening, the same day. I'm thinking of cleaning or replacing the Mass Air Flow sensor and the spark plugs.
Have you any advice for me?
have the same problem?
Sunday, December 13th, 2015 AT 7:46 PM