Oxygen Sensor, PO420A
jjolt
11-11-2004, 09:46 AM
The code PO420A came up on a OBD-II computer scanner. From what I understand, it's an oxygen sensor. However, there are two. Which one is it and where is it located?
richtazz
11-11-2004, 11:23 AM
po420a is "catalyst system efficiency below threshhold" That sounds like a bad converter to me. The oxygen sensor has nothing to do with catalyst efficiency.
Automotive Network, Inc., Copyright ©2026