EVAP System, Testing

-- Remove the filter hose from the fuel tank leak detection control module.

CAUTION:

Clamp only soft rubber lines when isolating a leak. To avoid risk of damage, never clamp hard plastic lines!

-- Plug or clamp the fuel tank leak detection control module filter port using Hose Clamps Up to 25 mm Dia.:VAS3094 or equivalent.

NOTE:

Vehicles equipped with the fuel tank leak detection control module may require one of two different test adapters that may vary depending on the model.

-- Attach Evaporative Emissions Tester - Adapter 57:KLI9210/57 or T adapter between the EVAP system and the EVAP Canister Purge Regulator Valve 1 -N80- .

NOTE:

No special tool T adapter is available at this time. The T adapter may have to be fabricated if it is required for testing.

-- Attach the test hose from the Evaporative Emissions Tester:KLI9210 to the adapter.

-- Set control valve -2- from "Hold" to "Test" .

Fig 1: Connect Vehicle Interface Hose To Self-Test Port

NOTE:

Calibrate Evaporative Emissions Tester:KLI9210 to 10 in. of water prior to connecting the to the vehicle.

-- Increase the current pressure until it reaches 10 in. H2O (25 mbar).

-- Monitor the pressure gauge -3- and the flow meter -4- . Allow the flow rate to decrease. If pressure builds to 10 in. H2O (25 mbar), the fuel system is full.

NOTE:

Depending on the level of fuel in the tank, it may take up to three minutes to notice a visible decrease in flow rate.

If any flow is shown on meter, a leak is present in the system. Locate the leak.
If no flow is shown on the meter, proceed with the following steps.

-- After the pressure has stabilized, set control valve -2- to "Hold" .

-- After five minutes, the pressure must not drop below 8 in. H2O (20 mbar).

If pressure drops below 8 in. of water in five minutes then find leak with the smoke tester, soapy water and/or isolating components by clamping them off individually.

If fuel system pressurization does not stabilize:

-- Verify all fuel system outlets have been sealed before continuing.

NOTE:

Any flow shown on flow meter indicates a leak.

If flow meter on tester registers flow near or above preset pressure:

CAUTION:

Clamp only soft rubber lines when isolating a leak. To avoid risk of damage, never clamp hard plastic lines!

-- Clamp off hose -arrow- leading from EVAP Canister Purge Regulator Valve 1 -N80- to intake manifold.

If no flow is present and the pressure drop is above 8 in. of water after five minutes:

-- Replace EVAP Canister Purge Regulator Valve 1 -N80- and repeat test before continuing.

If meter indicates no flow after test:

-- Perform a quality check and return vehicle to customer.

If flow continues, proceed as follows:

-- Refer to METHOD 1: LOCATE LEAK WITH SMOKE GENERATOR .

-- Refer to METHOD 2: LOCATE LEAK WITH ULTRASONIC TESTER .