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Thread: Code 420

  1. #1

    Default Code 420

    2002 Suburban 1500

    Which I think means: Bank 1, efficiency below threshold.

    So it's the cat or the down stream 02 sensor, right?

    Any way to test the sensor? If so how? Special tools required?

    Thanks for any insight.

    2008 Suburban 1500 LT with all the goodies.
    2009 2500 Crew Cab DMax LT Stock under the hood.....Nerf bars, cap and liner, de-badged, Husky Liners, CB, JVC woofer, bull bar. Roof lights

  2. #2

    Default

    Good idea, will try that.

    Can someone confirm that bank 1 is the drivers' side?

    2008 Suburban 1500 LT with all the goodies.
    2009 2500 Crew Cab DMax LT Stock under the hood.....Nerf bars, cap and liner, de-badged, Husky Liners, CB, JVC woofer, bull bar. Roof lights

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