my po420 code is on, on my 2006 buick lucerne. even if i clear it it comes within 2-4 days. really getting irritated. changed the catalytic converter and a 02 sensor .. please help
How to diagnose, repair, and info on symptoms and causes of a P0420 engine code which means the catalytic converter is no longer performing at a normal level.
2007 Lucerne CXL. and 1995 Lesabre currently, past 1973 Riviera, 1968 Riviera
On the code if a shop or if you are doing the repairs. There's two O2 sensors and it's possible, depending on sequence of repairs that the harness / O2 sensor may have been damaged or it's a poor quality aftermarket O2 sensors. A O2 sensor extender may resolve the problem, the type of catalytic converter may also be the cause. How many miles and what type of driving, highway or city, since installing?
Page 1 of 4: P0420 Catalyst Efficiency Below Threshold (Bank 1). How to Test Trouble Code P0420 (GM 3.8L). Symptoms of a P0420. What Causes the Catalytic Converter to Fail. Excessively Rich condition