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Steve
Steve, ASE Certified Tech
Category: Car
Satisfied Customers: 6914
Experience:  25 years working as a service technician
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today replaced o2 sensor down stream clear codes road test

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today replaced o2 sensor down stream clear codes road test car went 39 miles light can on again . should I have also had replaced the up stream o2 sensor.

Steve :

Thanks for trusting me to help you with your car today. I am a certified mechanic with over 25 years of experience. I look forward to working with you

Steve :

Unfortunately code p0420 is from the cat convertor is not reducing the pollution it should out the cat convertor, and the only way to eliminate the code is to replace the cat convertor. Sorry for the bad news.

Customer:

i was hoping that just the down stream o2 sensor would do it / the car belongs to my son-in law .what does the up stream o2 do?

Steve :

The upstream 02 sensor is the signal to the computer to tell it if the engine is running rich or lean. The downstream 02 sensor is to tell the computer if the cat convertor is working or not to reduce emissions.

Steve :

Unfortunately code p0420 is from the cat convertor is not reducing the pollution it should out the cat convertor, and the only way to eliminate the code is to replace the cat convertor. Sorry for the bad news.

Customer:

THANKS FOR HELP TODAY I WILL CHECK WITH THEM TO SEE WHAT THEY WANT TO DO . THE FIT IS NOT CHEAP

Steve :

You are very welcome. Sorry about the cost.

Steve :

Please rate the chat by clicking excellent service, and clicking the green submit button when it pops up. Thanks

Customer:

EXCELLENT SERVICE

Steve and 6 other Car Specialists are ready to help you
John,


Please rate the chat by clicking excellent service, and clicking the green submit button when it pops up. Thanks
Hi John,


I'm just following up with you to see how everything is going. Did my answer help?


Let me know,
Steve

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