2002 Toyota Camry Q&A

2002 Toyota Camry Question: catylitic convertor problem after an oxygen sensor makes check engine light

after the check engine light comes on and the code says catylitic convertor can this be caused by the number 1 oxygen sensor and the number 2 oxygen sensor being bad -
Answer 1
you may have circuit issues seek a diag and est to repair. could be several issues -
Answer 2
The #1 sensor mostly gives the ecu a signal for adjustments to fuel mixture. The #2 sensor was installed in 96 and later vehicles to monitor cat efficiency. thats why 96 and later vehicles are tested obd and 95 and earlier are tail pipe tested. If you have access to a multi meter and can attach it to the signal wire of the o2 sensor. Check that the voltage is steady above 500mv if the signal moves above and below 500mv, that is the sign of a bad cat. Tht car must be at full operating temp. When the signal moves to much the computer considers the cat no good. -