98 GMC SAVANA IS GIVING ME P0420 AND P0125

  • Tiny
  • lovetolaugh86
  • 1998 GMC Savana
  • 200,000 miles

98 GMC savana is giving me P0420 and P0125 is there one thing that can give both codes or are there different things wrongs with it. Given the year / model what are the most probable causes.

Thank You

Do you
have the same problem?
Yes
No
Monday, April 9th, 2012 AT 6:27 AM

1 Reply

  • Tiny
  • fixitmr
  • Member

P0125 coolant temp to low for closed loop mode. P0420 catalyst efficiency below threshold. I would fix the first and see if the second goes away. Could be your thermostat or the temp sensor.

Was this
answer
helpful?
Yes
No
Monday, April 9th, 2012 AT 6:49 AM

Please login or register to post a reply.

Similar Questions