Q: My check engine light is on it is saying catalytic system bank 1 is below threshold. What does that mean and do I have to change t

asked by on September 15, 2017

My check engine light is on it is saying catalytic system bank 1 is below threshold. What does that mean and do I have to change out the 02 sensors? Sometimes when I'm sitting at the read light I can smell fumes.
If I get an emissions test done will that tell me what's going on?

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