O2 Sensor Readings P0420 Code
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6th Gear
Joined: Apr 2023
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From: TX
O2 Sensor Readings P0420 Code
My 2002 ES300 (70K mi) has it’s check engine light on and throwing a P0420 code (Below Threshold Bank 1)
I plugged in my OBD code reader and checked the O2 sensor live data. Live Data 02 sensors, 2000 rpm’s at operating temp read as follows;
02B1S1 3.25 steady
02B2S1 3.25 steady
02B1S2 0.0-0.9 erratic
02B2S2 0.75-0.78 steady
Obviously the code is seeing the erratic reading from B1S2
Asking questions to a few mechanics I get different opinions but most want to go straight to replacing the Cat. I also read that the most common issue could be a simple vacuum hose issue being the car is 20yr old. Truly a difference in price and how to approach the fix.
Has anyone else run into this issue or know of common P0420 fixes seen with ES300?
I plugged in my OBD code reader and checked the O2 sensor live data. Live Data 02 sensors, 2000 rpm’s at operating temp read as follows;
02B1S1 3.25 steady
02B2S1 3.25 steady
02B1S2 0.0-0.9 erratic
02B2S2 0.75-0.78 steady
Obviously the code is seeing the erratic reading from B1S2
Asking questions to a few mechanics I get different opinions but most want to go straight to replacing the Cat. I also read that the most common issue could be a simple vacuum hose issue being the car is 20yr old. Truly a difference in price and how to approach the fix.
Has anyone else run into this issue or know of common P0420 fixes seen with ES300?
Lead Lap
Joined: Nov 2019
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From: Michigan
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nicos1
ES - 1st to 6th Gen (1990-2018)
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