EVAP SYSTEM, DIAGNOSIS WITH KLI9210 EVAP TESTER
Special tools and workshop equipment required
- Evaporative Emissions Tester KLI 9210
- Vehicle Diagnostic Tester
- Hose Clamps Up to 25 mm Dia. VAS 3094
Description
The leak detection threshold has recently changed from 1.0 mm (0.040 in.) to 0.5 mm (0.020 in.). These changes to EPA regulations regarding Evaporative Emission (EVAP) system integrity indicated that additional resources for more accurate EVAP system diagnosis are necessary.
The KLI 9210 EVAP Tester allows testing using nitrogen to pressurize the EVAP system and a smoke generator or ultrasonic tester to locate the source of EVAP system concerns.
The following procedure will outline general use of the KLI 9210 EVAP Tester. It is intended as a guideline, as EVAP systems vary between models.
Test EVAP System Using Leak Detection Pump (LDP) -V144- (MY 1998 and later)
For vehicles without LDP, proceed to Perform EVAP Tester Self-Test.
For vehicles with LDP
Perform leak test using vehicle diagnostic tester and Basic Setting mode.
If vehicle fails above test (System not OK)
Verify fuel cap is properly closed; repeat test.
If System OK after re-test
Erase Diagnostic Trouble Code (DTC) memory (if necessary).
Repeat test several times to ensure proper EVAP system operation (remove and re-install fuel cap before each test).
Perform quality check and return vehicle to customer.
Note. If the vehicle passes the above EVAP system test, DTCs may be sporadic; the entire EVAP system should be carefully inspected.
If the vehicle diagnostic tester continues to indicate System not OK after re-test, proceed to next step.
Perform EVAP Tester Self-Test
Note. Always perform system self-test of KLI 9210 prior to use to ensure that there are no leaks. Refer to KLI9210 instruction information for specific instructions.
Connect vehicle interface hose to self-test port -1-, ensuring that fitting is finger-tight. Over-tightening will damage fitting.
Scheme 167
Turn control valve -2- to Test.
Gauge -3- should read 14 ± 1 in. of water.
If gauge does not read 14 ± 1 in. of water
Verify that valve on EVAP tester nitrogen cylinder is open and that cylinder has sufficient pressure before continuing.
Turn fine adjust regulator knob (-arrow-) until gauge reads 14 in. of water; tighten lock nut.
Scheme 168
Note. If gauge still does not read within above range, contact K-Line Customer Service - Technical Support for additional instructions before continuing.
Check flow meter -4-. (upper illustration).
Meter must indicate no flow.
Turn control valve to Hold position.
Check gauge.
Gauge must hold pressure
If gauge leaks down
Verify that vehicle interface hose is firmly seated and repeat previous six steps before continuing.
If gauge continues to leak down
Use ultrasonic tester (described later) to locate and repair leak before continuing.
Note. If the leak cannot be located or repaired, contact K-Line Customer Service - Technical Support.
Calibrate KLI 9210
Determine vehicle leak threshold
To MY 2000: leak threshold 0.040 in.
From MY 2001: leak threshold 0.020 in.
Attach test hose to appropriate preset port (black -arrows-).
Scheme 169
Turn control valve from Hold to Test.
Set flow meter flag (white -arrow-) at indicated value on flow meter.
Turn control valve to Hold; remove test hose.
Test Fuel Cap
Connect fuel cap tester to hose.
Screw fuel cap tightly to cap receiver (-arrow-).
Scheme 170
Turn control valve to Test.
Read flow meter on tester.
If no flow is indicated
Proceed to Test LDP For Internal Leaks.
If flow is indicated
Replace fuel cap and re-test.
If new fuel cap shows no flow
Repeat leak test, with new fuel cap installed, using vehicle diagnostic tester and Basic Settings mode.
If Leak Test shows 'System OK"
Perform quality check and return vehicle to customer.
Test Leak Detection Pump (LDP) -V144- For Internal Leaks
If vehicle is not LDP-equipped, proceed to Test EVAP System.
Clamp off LDP outlet (EVAP side) using VAS 3094 or equivalent.
| CAUTION | Clamp only soft rubber lines when isolating a leak. To avoid risk of damage, never clamp hard plastic lines! |
Repeat Leak Test using vehicle diagnostic tester and Basic Setting mode.
Vehicle diagnostic tester should immediately indicate System OK.
Repeat test several times to verify result.
If test continues to indicate System OK, remove clamp and proceed to Test EVAP System.
If vehicle diagnostic tester indicates System not OK
Replace LDP and repeat test.
If vehicle diagnostic tester indicates System OK after LDP is replaced and test result is verified
Perform quality check and return vehicle to customer.
Test EVAP System
If vehicle is not LDP-equipped
Plug or clamp EVAP canister outlet and proceed to step continued for all vehicles (below).
If vehicle is LDP-equipped
Plug or clamp LDP inlet (filter side) using VAS 3094 or equivalent.
Attach fuel cap adapter to filler neck (-arrow-) and test hose to adapter.
Scheme 171
Turn control valve from Hold to Test.
Allow fuel system to pressurize.
Note. Fuel system pressurization depends on volume of fuel system and amount of fuel in tank.
If fuel system pressurization does not stabilize
Verify all fuel system outlets have been sealed before continuing.
| CAUTION | Clamp only soft rubber lines when isolating a leak. To avoid risk of damage, never clamp hard plastic lines! |
Note. Any flow shown on flow meter indicates a leak. Flow before flow meter flag set at vehicle leak standard may indicate a sporadic DTC.
If flow meter on tester registers flow near or above preset pressure
Clamp off hose (-arrow-) leading from EVAP canister purge regulator valve 1 -N80- to intake manifold (pictured: AHA engine in A6).
Scheme 172
If flow stops
Replace EVAP canister purge regulator valve 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
Method 1: Locate Leak With Smoke Generator
Connect leads from smoke generator to vehicle battery.
Use smoke generator trigger to charge fuel system with smoke.
Inspect complete EVAP system for escaping smoke.
Method 2: Locate Leak With Ultrasonic Tester
Scheme 173
General search: tester only
Localized search: tester with extension (on left in illustration)
If leak cannot be located
Disconnect and plug or clamp shut EVAP lines to isolate fuel tank, using VAS 3094 or equivalent, before continuing.
| CAUTION | Clamp only soft rubber lines when isolating a leak. To avoid risk of damage, never clamp hard plastic lines! |
If flow stops
Reconnect EVAP lines to search area that was isolated.
If leak or source of fuel odor cannot be found
Contact Audi Dealer Technician Helpline.
| CAUTION | Under no circumstances should the vehicle be returned to the customer without proper diagnosis and repair. |
When leak has been located
Repair leak and repeat EVAP system test.
Perform quality check and return vehicle to customer.
Note. Because leak may be at top of fuel tank, it may not be possible to locate through fuel pump/sending unit access plate. Fuel tank may need to be lowered to locate the leak.
SPECIAL TOOLS
Special tools and workshop equipment required
Scheme 174
- Hose Clamps Up to 25 mm Dia. VAS 3094
- Not illustrated
- Evaporative Emissions Tester KLI9210
- Vehicle Diagnostic Tester