EVAP system leak inspection using leak tester

Perform the following SST (EVAP System Tester 134-01049A) self-test:
NOTE:
- If the tester does not work correctly during the self-test, refer to the tester operators manual for a more detailed self-test procedure.
1. Verify that the control valve on the panel is in the HOLD position, then open the nitrogen bottle valve.
2. Connect the vehicle interface hose (part of the SST) to the SELF-TEST port located on the control panel. Hand tighten the fitting. (Do not overtighten).
3. Turn the control valve to the TEST position.
4. The gauge should read 331-381 mm {13-15 in} of water.
  
  Fig 1: Connecting Vehicle Interface Hose (Part Of SST) To Self-Test Port Located On Control Panel
  - If the gauge is not reading in this range, adjust the pressure by turning the black knob on the low pressure regulator at the nitrogen bottle.
5. Turn the control valve to the HOLD position.
6. Verify that the gauge holds pressure and that the flow meter reads no flow.
  - If there is no drop in pressure and no flow, the tester passes the self-test.
  - If the gauge leaks down, refer to the tester operators manual.
Connect the SST to the vehicle.
1. Verify that the control valve on the panel is in the HOLD position then open the nitrogen bottle valve.
2. Remove the fuel-filler cap from the vehicle.
  - If the fuel-filler cap is not a MAZDA part or equivalent, replace it.
  NOTE:
  - INSPECT FUEL FILLER CAP AND FILLER NECK
    
    Visually inspect for damage, insufficient sealing, rust, cracks or warps of filler cap and filler neck.
    
    Repair or replace if necessary.
3. Connect the receiver assembly (SST : 134-01059) to the vehicle cap test hose assembly (part of the SST ) and the fuel-filler cap from the vehicle.
4. Connect the cap adaptor (SST : 134-01058) to the vehicle cap test hose assembly (part of the SST ) and to the fuel-filler neck.
5. Connect the vehicle interface hose (part of the SST ) to the center fitting of the vehicle cap test hose assembly (part of the SST ).
  
  Fig 2: Identifying Cap Adapter, Receiver Assembly, Vehicle Cap Test Hose Assembly And Vehicle Interface Hose
Connect the M-MDS to the DLC-2.
Switch the ignition to ON (engine off).
Using the M-MDS request the PCM on-board device control (Mode08) to close the canister vent value.
NOTE:
- The canister vent value is closed for 10 min unless any of the following actions are done:
  - The engine is started.
  - The ignition is switched to off.
Make sure the control valve on the 134-01049A is in the HOLD position and that the valve on the cylinder of nitrogen gas is open.
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
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.
Verify 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 preset 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:
- Turn the control valve to the HOLD position, then disconnect the SST .