# O2 sensor problems : Toyota camry
**URL:** https://forums.speedlife.net/t/o2-sensor-problems-toyota-camry/11330
**Category:** NYSpeed Automotive
**Created:** [April 27, 2006, 7:21am UTC](https://forums.speedlife.net/t/o2-sensor-problems-toyota-camry/11330 "2006-04-27T07:21:33Z")
**Posts on this page:** 5
**Page:** 1
### Author:  [@Daddie](https://forums.speedlife.net/u/Daddie)
#### Post date: [April 27, 2006, 7:21am UTC](https://forums.speedlife.net/t/o2-sensor-problems-toyota-camry/11330/1 "2006-04-27T07:21:33Z")
2000 Toyota Camry, 4 cylinder, California emmisions car.
The 2nd bank (by the cat) 02 sensor (pre cat) seems to not be showing up on my friends scanner at all. Car throws a check engine light. Code is something to do with a failed emmisions component.
Called toyota, has 2 kinda of 02 sensors. An A/F one (as they call it) and a regular one.
Guy at toyota doesn’t know which one to put in. (even with vin)
Which one goes in there? (Pre cat, right by cat)
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### Author:  [@MaximaSE98](https://forums.speedlife.net/u/MaximaSE98)
#### Post date: [April 27, 2006, 7:29am UTC](https://forums.speedlife.net/t/o2-sensor-problems-toyota-camry/11330/2 "2006-04-27T07:29:06Z")
i woudl say since its a CA Emissions car i would say A/F one
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### Author:  [@66impalass](https://forums.speedlife.net/u/66impalass)
#### Post date: [April 27, 2006, 7:41am UTC](https://forums.speedlife.net/t/o2-sensor-problems-toyota-camry/11330/3 "2006-04-27T07:41:04Z")
Ca car, pre cat should be the A/f one as that is the one that controls the fuel mixture for the motor. The “regular” one should be there to just check that the cat is functioning properly
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### Author:  [@Daddie](https://forums.speedlife.net/u/Daddie)
#### Post date: [April 27, 2006, 8:44am UTC](https://forums.speedlife.net/t/o2-sensor-problems-toyota-camry/11330/4 "2006-04-27T08:44:41Z")
Why would not “register” on the scan tool?
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### Author:  [@66impalass](https://forums.speedlife.net/u/66impalass)
#### Post date: [April 27, 2006, 12:10pm UTC](https://forums.speedlife.net/t/o2-sensor-problems-toyota-camry/11330/5 "2006-04-27T12:10:57Z")
cheap scan tool??
have you tried more than one scan tool
also i just noticed, how can a 4 cylinder have a second bank