2004 Chevy Silverado Code P0420 problems

Tiny
PSBOWLER
  • MEMBER
  • 2004 CHEVROLET SILVERADO
  • V8
  • 4WD
  • AUTOMATIC
  • 87,612 MILES
This code keeps coming up and we are running out of ideas how to fix it. Convertor is less than a year old and seems to be okay. O2 sensor #1 changed shortly after new convertor installed. O2 sensor #2 changed 2 weeks ago. Just pulled freeze frame data out and here is what it gave:

Fuel Sys 1 OL-Drive
Fuel Sys 2 OL Drive
Calc Load (%) 1.96
ECT (F) 195
STFT B1(%) 0.78
LTFT B1(%) 6.25
STFT B2(%) 0.78
LTFT B2(%) 6.25
MAP(inHg) 11.22
Eng RPM 537
Veh Speed 0
MAF(lb/min) 0.73
TPS(%) 9.41
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Thursday, March 11th, 2010 AT 12:08 PM

4 Replies

Tiny
MERLIN2021
  • EXPERT
There is a technical service bulliten from GM to thier dealer about this. I will email it to you.
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Thursday, March 11th, 2010 AT 3:22 PM
Tiny
PSBOWLER
  • MEMBER
Thanks, but no dice. Checked the wiring and no rust anywhere. Probably going to take it to the dealer this week and get it looked at again. Appreciated your quick response, though.
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Monday, March 15th, 2010 AT 4:17 PM
Tiny
2CARPROS LINSEY
  • MEMBER
Thank you for using 2CarPros. Com. We appreciate your donation and look forward to helping you in the future.
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Monday, March 15th, 2010 AT 5:13 PM
Tiny
MERLIN2021
  • EXPERT
Thanks Lindsey.
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Thursday, March 18th, 2010 AT 4:08 PM

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