1998 Subaru Outback catalytic converter

1998 SUBARU OUTBACK
231,000 MILES • 4 CYL • AWD • AUTOMATIC
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SCUDERI_D
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  • 1 POST
code P0420= cat. system efficiency below threshold (bank 1)

California car- Is problem in front or rear cat?
Jun 1, 2010 at 8:59 AM
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BLUELIGHTNIN6
  • ✓Experienced Mechanic
  • 16,542 POSTS
could be anywhere. 0420 for Subaru Outback simply indicates that the cat. converter system is not operating correctly, it does not pinpoint location. check between cylinder head and front exhaust pipe, between front exhaust pie and front cat. converter, and between front and rear cat. converter for exhaust leaks or air suction caused by loose or missing nuts/bolts or damage to exhaust system.
Jun 1, 2010 at 4:32 PM
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