Q: Failed a smog test

asked by on September 30, 2016

I took the car to get a smog check and it has failed the NO part the first time and the HC the second time. I took it two different mechanics and one tells me its the catalytic converter and o2 sensor. The other one says the engine is burning too much oil. I did the oil change about 2 months ago oil seems to be doing okay. This car has had the catalytic changed 4 years ago by my brother the first time it failed the smog. Im just wondering if to change the catalytic converter and 02 sensor would make any difference for the smog. I have no other issues with it. The check engine light is not on.

My car has 175000 miles.
My car has an automatic transmission.

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