Vapor Recovery System Leak Test (Discovery 1)

The old system

Required equipment

compressed nitrogen cylinder (do not use air!) pressure gauge 0 - 900 mm H₂ O hoses and tee

Examination

1. Make sure there is at least 8 liters of fuel in the tank.

2. Disconnect the vapor separator hose from the battery.

3. Connect the hose and battery through a tee with a nitrogen cylinder.

4. Create a pressure of 670-700 mm H₂ O, wait until the pressure stabilizes and close the cylinder valve.

5. After 2.5 minutes, read the pressure gauge. If the pressure has decreased by more than 60 mm H₂ O, there are leaks in the system. In a completely sealed system, the pressure may increase slightly.

6. To locate leaks, apply a soap solution to all hose connections and fittings. Apply pressure and locate the leak by bubbling.

New system

1. Connect the diagnostic tester to the vehicle connector and identify the fault codes related to the evaporative emission system.

2. Check the relevant system components.

3. Replace or repair defective components.

4. Conduct running tests, see below.

5. Make sure there are no faults.

6. Use a leak detector to locate the leak.

7. After troubleshooting, proceed to step 4.