1999 Chevy Suburban OBD Code/wet weather

1999 CHEVROLET SUBURBAN
175,000 MILES • V8 • 2WD • AUTOMATIC
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JIMST
  • MEMBER
  • 1 POST
driving in rain/wet weather..."check eng light" illuminates. Code P0430 on code reader...Code reader turns out light...After 10-20 miles CEL returns.As weather clears up (dryer) the problem disappears, and does not return until the next rain/wet weather cycle....... HELP
Nov 16, 2009 at 10:57 AM
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PEAR69
  • CAR REPAIR CONTRIBUTOR
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A p0430 means that one or both of your oxygen sensors on Bank 2 is either, sensing that there is a problem with the catalyst system efficiency, -and/ or - the oxygen sensor is failing. It could also mean that there is an exhaust leak..
First, check for exhaust leaks.
Second, test the two oxygen sensors on bank 2. It is a good idea to just test all 4 oxygen sensors. If they pass ---check all the wiring and connectors associated with the oxygen sensors. Third, have an air flow test performed on both catalytic converters to determine which one (or both) may be not working..
If all of that fails we will move on to the fuel delivery side of things...
Nov 17, 2009 at 1:12 AM
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