Question about 2002 Buick Rendezvous
I have 2002 avalanche and my engine light came on so i pulled the code and it said 0420 which means o2 senser or what else could this be
There are a number of things that could be causing this p0420 catalyst efficiency
code. The most common thing is the catalytic converter itself is no longer
functioning properly. The other likely thing is the rear O2 (oxygen) sensor
is no longer working properly. Other things could include exhaust leaks, damaged
exhaust pipes, damaged O2 sensor wiring/connectors, plugged catalytic converter,
The easiest thing to do first is a visual check of things. Visually inspect the exhaust system for leaks, check the catalytic converter for dents, holes, severe discoloration, and check for a rattle inside. If any of those symptoms are there, the converter likely needs replacement. Then, visually inspect the downstream O2 sensor (behind the converter). Check for broken wires, obvious faults, etc. If all that checks out, you'll want to check the operation of the O2 sensor. To do that, you'll need access to a scan tool or oscilloscope. Check that the waveform is pretty steady. If the reading fluctuates then the sensor is likely bad and will need to be replaced.
Good luck and hope this helps.
Posted on Nov 19, 2009
Testimonial: "fast response. and to the point ,love that"
This typically means the catalytic converter is not performing within the specified range. Often though, the O2 sensor itself is failing. You will need a scanner that reads the O2 sensors to determine whether the sensor is at fault. If you have one, let me know so I can further assist you.
Posted on Nov 19, 2009
a 6ya expert can help you resolve that issue over the phone in a minute or two.
best thing about this new service is that you are never placed on hold and get to talk to real repairmen in the US.
the service is completely free and covers almost anything you can think of (from cars to computers, handyman, and even drones).
click here to download the app (for users in the US for now) and get all the help you need.
Posted on Jan 02, 2017
Tips for a great answer:
Feb 22, 2013 | 2002 Chevrolet Avalanche
Jun 27, 2012 | 2002 Chevrolet Avalanche
Feb 27, 2012 | 1993 Ford Taurus
Mar 06, 2011 | Chevrolet C1500 Cars & Trucks
Sep 11, 2010 | 2002 Chevrolet Avalanche
Apr 07, 2010 | 2002 Chevrolet Avalanche
Jun 02, 2009 | 2001 Dodge Ram 1500 Truck 2WD
363 people viewed this question
Usually answered in minutes!
Step 2: Please assign your manual to a product: