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Hello all, I have a 2004 Solara SLE 2.4 that is having a problem passing the California Smog test due to the Catalyst monitor not being ready. I previously had a P2238 code and replaced the AFR sensor then proceeded replace the spark plugs, o2 and MAF sensor, all Denso. I also replaced the thermostat and battery and drove for around 600 miles. If this helps the long term fuel trim at idle 670 rpms is around 7.8, the AFR is 9.7:1 and all other monitors are ready with no codes or pending codes. Is this an indication of a failed catalytic converter or is there another direction I should be taking? Any help is truly appreciated.
 

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2011 Camry LE 2.5L
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If you have an infrared thermometer, try checking temps right before and after the cat. After should be 200° F. higher give or take, much hotter in any case. Youtube videos on that. Your AFR seems very low. The O2 sensors are in normal range?
 

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The 2.4L 2AZ is known to burn oil and over time starts to clog the catalyst and affect its efficiency. You can remove the upstream O2 sensor and borescope the cat to see if this is the issue. LT fuel trims aren't a good indicator. Is the ST fuel trim showing negative, especially under load or hard acceleration?
 

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If you have an infrared thermometer, try checking temps right before and after the cat. After should be 200° F. higher give or take, much hotter in any case. Youtube videos on that. Your AFR seems very low. The O2 sensors are in normal range?
Thanks for the reply, I'll have to go pick a thermometer up and check. I was thinking the same thing about the AFR, from what I understand shouldn't it be in the 14.7:1 range? I'm not sure what to do to correct it or what might be causing this issue.
 

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The 2.4L 2AZ is known to burn oil and over time starts to clog the catalyst and affect its efficiency. You can remove the upstream O2 sensor and borescope the cat to see if this is the issue. LT fuel trims aren't a good indicator. Is the ST fuel trim showing negative, especially under load or hard acceleration?
Thanks for the reply, yes the short term fuel trim goes negative around -15 or so, sometimes more when i accelerate. I know bank 2 o2 sensor is all over the place at idle, no real steady oscillation.
 

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Thanks for the reply, yes the short term fuel trim goes negative around -15 or so, sometimes more when i accelerate. I know bank 2 o2 sensor is all over the place at idle, no real steady oscillation.
That is certainly looking like a clogged catalytic converter. To confirm, remove upstream o2 sensor and install back pressure tester. Run engine and check pressure at idle, then when revving the motor. They can be had for pretty cheap online. Autozone has one for $70. If you have a borescope or smartphone scope camera, you can put inside the catalyst and look at the honeycomb. You may see areas that are clogged with white ash.
 

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That is certainly looking like a clogged catalytic converter. To confirm, remove upstream o2 sensor and install back pressure tester. Run engine and check pressure at idle, then when revving the motor. They can be had for pretty cheap online. Autozone has one for $70. If you have a borescope or smartphone scope camera, you can put inside the catalyst and look at the honeycomb. You may see areas that are clogged with white ash.
I know it's been a while but thanks for the information, I finally got around to ordering a bore scope and it was pretty much all white ash on top from what I could see. Ended up replacing the catalytic converter and passed smog the next day.
 

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I know it's been a while but thanks for the information, I finally got around to ordering a bore scope and it was pretty much all white ash on top from what I could see. Ended up replacing the catalytic converter and passed smog the next day.
Cool!!! Happy to see this worked out 4 u. The 2AZ likes to burn sum earl....
 
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