Conditions for Setting the DTC

1999 GMC Forward Control 5.7 R, AutomaticSECTION Conditions for Setting the DTC
WARNING: This page is about a different car, the 2003 Pontiac Vibe. However, it is still accessible from the selected car via links, so may be relevant.

The pressure indicated in EVAP canister and fuel tank does not drop when EVAP canister purge valve is ON. Or, pressure indicated in EVAP canister remains very low when compared to atmospheric pressure when EVAP canister purge solenoid valve is OFF.

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.