Conditions For Setting DTC

1999 GMC Forward Control 5.7 R, AutomaticSECTION Conditions For Setting DTC
WARNING: This page is about a different car, the 2002 Pontiac Grand Prix, 2002 Chevrolet Malibu, and 2002 Buick Century. However, it is still accessible from the selected car via links, so may be relevant.

DTC will set if either of the following conditions are present :

  • The HO2S 1 rich-to-lean transition time takes longer than 105 milliseconds.
  • The HO2S 1 lean-to-rich transition time takes longer than 95 milliseconds.

RENDER: 1.0x

NO RELATED

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When to See a Mechanic

Stop DIY work and contact a certified mechanic immediately if any of the following apply:

  • β€’ You smell fuel, burning insulation, or see smoke.
  • β€’ Brakes feel soft, pull hard to one side, or make grinding noises.
  • β€’ The engine overheats, stalls repeatedly, or misfires under load.
  • β€’ You are missing required tools, torque specs, or safe lifting equipment.
  • β€’ You are not confident in the next step or safety outcome.