Mazda CX-9 Grand Touring 2009 Manual page 1410

2008 ENGINE Symptom Troubleshooting (MZI-3.7) - Mazda CX-9
Fig. 21: Inspecting Fuel Filler Cap & Filler Neck
Courtesy of MAZDA MOTORS CORP.
NOTE:
6. Make sure the control valve on the 134-01049 is in the HOLD position and that the valve on the cylinder
of nitrogen gas is open.
7. Turn the control valve to the open position and let the system fill. You should note a drop in the gauge
pressure along with the flow meter being pegged at maximum flow for several minutes depending on how
full or empty the fuel tank is, and how long it takes to completely fill and pressurize the evaporative
emissions system hoses.
8. If the gauge and the flow meter do not settle to a measurable level after 2-3 min, then refer to the Mazda
Workshop Manual to verify that the canister vent valve is properly closed. If canister vent valve is
properly closed. The EVAP system has large leakage. Check for leakage and repair as necessary.
9. Verify the pressure gauge and flow meter reading to determine if there is an evaporative emissions leak:
NO EVAPORATIVE LEAK:
The flow meter registers "zero flow" and the pressure gauge returns to the pre-set pressure of 356
mm {14 in} of water (H2O).
EVAPORATIVE LEAK:
The pressure does not return to the preset level of 356 mm {14 in} of water (H2O) when measuring
the flow. See "SETTING LEAK STANDARD FOR TESTING" (.020 to .040 inch H2O) of the
Evaporative Emissions Tester operators manual (134-01067).
NOTE:
2008 Mazda CX-9 Grand Touring
The canister vent value is closed for 10 min unless the following any
actions are done:
The engine is started.
The ignition switch is turned off position.
Turn the control valve to the HOLD position then disconnect the SST.