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Does oxygen sensor affect catalytic converter?
A faulty O2 sensor can trigger a check engine light and also register as a failed catalytic converter, random cylinder misfires, camshaft/crankshaft positioning codes, and even transmission codes. Typically a replacement oxygen sensor can save you a lot of headaches and misdiagnosis.
How do I know if my catalytic converter is bad or O2 sensor?
The check engine light often appears if your catalytic converter is clogged, although since the O2 sensor reports slower (because it measures efficiency over a longer period of time than other sensors), you might get a “check engine” light for something else like engine misfires, before you get a check engine light for …
Why is a P0420 trouble code almost never a bad oxygen sensor?
NOTE: This is why a P0420 trouble code is almost never a bad oxygen sensor — because the ECM has already tested the downstream sensor. If it isn’t responding properly, it will set a trouble code. The same applies to the upstream sensor. If it’s not switching rapidly, the ECM will set an O2 sensor related trouble code
What does P0420 mean on a catalytic converter?
Here’s the official definition of a P0420 trouble code: P0420 Catalyst System Efficiency Below Threshold (Bank 1). What the code is telling you is that the catalytic converter has failed an efficiency test. In 99.5% of the cases, this code means that the catalytic converter itself is bad and must be replaced.
How does a P0420 readiness monitor test work?
During a P0420 readiness monitor test, the ECM will purposely and rapidly command a very rich and very lean mixture to force the downstream sensor to read the excess fuel or oxygen. Then it will stop the excessive air/fuel and watch the downstream sensor again, looking for a steady reading.
What is the cel code for a 2003 Vibe?
My CEL is on and the code reads P0420 on a 2003 Vibe. There are apparently three options: This is most likely beyond my mechanical abilities (been bitten), but I’d like to get the part from a reputed maker (been bitten there too), and take it to my mechanic.