Safety Warning
DIY auto repair can cause serious injury, fire, or vehicle damage. These guides are for informational purposes only. Always follow OEM torque specs, wear PPE, and consult a certified mechanic if you are unsure. You are solely responsible for your safety.
2000 Chevrolet Express 3/4 Ton Van V8-305 5.0L VIN M SFIFACTORY OEM SERVICE PROCEDURE
EVAP Duty Cycle
RANGE (0-100 PERCENT):
The scan tool indicates the [1][2]EVAP duty cycle that the VCM is commanding. The EVAP duty cycle is a pulse width modulated voltage applied to the purge valve which is displayed as a percentage. A high percentage of EVAP duty cycle would indicate near maximum canister purging.
The scan tool indicates the [1][2]EVAP duty cycle that the VCM is commanding. The EVAP duty cycle is a pulse width modulated voltage applied to the purge valve which is displayed as a percentage. A high percentage of EVAP duty cycle would indicate near maximum canister purging.
Factory Service Tools
Use the Manual With the Right Hardware
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When to See a Mechanic
Stop DIY work and contact a certified mechanic immediately if any of the following apply:
- • You smell fuel, burning insulation, or see smoke.
- • Brakes feel soft, pull hard to one side, or make grinding noises.
- • The engine overheats, stalls repeatedly, or misfires under load.
- • You are missing required tools, torque specs, or safe lifting equipment.
- • You are not confident in the next step or safety outcome.
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