replaced catalytic converter and both o2 sensor still have p0420.
Nov 4, 2021 at 9:37 AM
Code p0240
2003 GMC ENVOY
DIGGOD1
- MEMBER
- 1 POST
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JACOBANDNICKOLAS
- ✓ASE Certified Mechanic
- 110,193 POSTS
Hi,
The code simply indicates the converter is no longer doing its job. Did you reset or clear the code? It should reset itself after three consecutive ignition cycles without a problem. Are there any other codes stored?
Since everything is new, we may need to confirm the sensors are working properly. There could be a wiring issue.
Take a look through this link. It explains what to test.
https://www.2carpros.com/articles/how-to-test-an-oxygen-sensor-02-sensor
Let me know if you have a live data scanner and if there are any other codes stored.
Take care,
Joe
The code simply indicates the converter is no longer doing its job. Did you reset or clear the code? It should reset itself after three consecutive ignition cycles without a problem. Are there any other codes stored?
Since everything is new, we may need to confirm the sensors are working properly. There could be a wiring issue.
Take a look through this link. It explains what to test.
https://www.2carpros.com/articles/how-to-test-an-oxygen-sensor-02-sensor
Let me know if you have a live data scanner and if there are any other codes stored.
Take care,
Joe
Nov 4, 2021 at 7:45 PM
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