p0420 code

2001 JAGUAR X-TYPE
118,000 MILES • 2.5L • V6 • AWD • MANUAL
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KRONOSONE
  • MEMBER
  • 3 POSTS
Hi,

My car keeps throwing a p0420 code on my code reader, but no engine light is on. Should I be worried? How can I diagnose the fault further?

Thanks,

Andy
Jul 17, 2017 at 10:39 PM
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MHPAUTOS
  • ✓ASE Certified Mechanic
  • 31,937 POSTS
  • ASE Certified Mechanic
the O2 sensor may be failing, get a live data read and see if the sensor is working. When they fail the PCM will go full rich and you will use more fuel. If that sensor is okay, you may need to get an exhaust reading done to see if the catalytic converter has failed as well.
Jul 18, 2017 at 5:41 AM
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