OBD code PO420
venturenot
05-19-2009, 04:54 PM
PO 420; Catalyst System Efficiency Below Threshold (Bank 1). Anyone have any experience with this code? Is this definitely a catalytic converter problem or could it be something else.
Thank you
Thank you
roadrunner2
05-20-2009, 12:39 AM
PO 420; Catalyst System Efficiency Below Threshold (Bank 1). Anyone have any experience with this code? Is this definitely a catalytic converter problem or could it be something else.
Thank you
Have the post-cat o2 sensor tested before changing the cat, as the electrical connection or the sensor itself may be faulty. This sensor (if working properly) sends a signal to the computer when the cat becomes deficient.
Make sure the engine has been run up to the operating temp before testing the sensor.
The codes only point you in the direction of a possible faulty system.
Year/mileage? Any visible damage to cat?
Thank you
Have the post-cat o2 sensor tested before changing the cat, as the electrical connection or the sensor itself may be faulty. This sensor (if working properly) sends a signal to the computer when the cat becomes deficient.
Make sure the engine has been run up to the operating temp before testing the sensor.
The codes only point you in the direction of a possible faulty system.
Year/mileage? Any visible damage to cat?
venturenot
05-20-2009, 03:54 PM
It is a 1998 extended van with 153,000. There is no visible damage to converter.
toni1595
05-20-2009, 07:16 PM
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