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Subaru RS 2009 MY10 P0420 error code?

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Hi,

 

I am currently having a issue with a P0420 Code,  apparently some guys have already had success with

the fix was "detailed" as "PAC FILE UPDATE FOR CATALYTIC SYSTEM".

 

Has anyone else had this code and done this fix for the issue?

 

 

Don't know of this "fix".

Generally (tho not always) this code is related to the 2nd O2 sensor. The fix for this is to replace that sensor. Many have resolved this issue with a spark plug spacer .if there is room to mount.

Do search for P0420.

 

O.

Edited by ocei77

There was an update available from the dealer which changes the diagnostic monitor and how it determines the conditions for setting this code.

 

More likely, you just need to do a tune-up and make sure you have no vacuum leaks.

Look up Cardocs P0420 thread on SubaruOutback.org

Lots of good info there on what to look for and what to change before replacing expensive cats or O2 sensors. Its a 90+ page thread but lots of good info in the first few pages.

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