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Double Check-Valve, Checking



Double Check-valve, Checking

NOTE: Fuel rail, assembly overview.

Recommended special tools and equipment







- Hand vacuum pump VAS 6213

Work procedure







- Disconnect 3-pin connector from Low Fuel Pressure Sensor -G410- and 2-pin connector from Evaporative Emission (EVAP) Canister Purge Regulator Valve -N80- (-arrows-).
- Disconnect vent line -A- from Evaporative Emission (EVAP) Canister Purge Regulator Valve -N80- (-B-).







- Connect hand vacuum pump on vent line to double check-valve -arrow-.
- Operate hand vacuum pump several times:

Vacuum must build up.

If no vacuum builds up:
- Replace double check-valve.
- Erase DTC memory of Engine Control Module (ECM). Diagnostic Mode 04 - Erase DTC Memory
- Generate readiness code. Monitors, Trips, Drive Cycles and Readiness Codes