I keep getting an eml thrown up. 

The code I'm getting is P0420 

"catalyst system efficiency below threshold (bank 1)"

any one else had this or know exactly what it means? 🤔

I believe that's triggered if the pre and post cat O2 sensors reading are similar(cat appears to not be doing it's job)

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7 minutes ago, mattiekane said:

I believe that's triggered if the pre and post cat O2 sensors reading are similar(cat appears to not be doing it's job)

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There's one in the downpipe and one between the downpipe and centre section on the hawks I think. Any way of telling which one needs replacing?

What are you using to code read?

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https://allwheeldriveauto.com/subaru-check-engine-light-and-code-p0420-explained/

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@mattiekane torque pro 👍