EuroVan 2.8L (Engine Code AXK)
NOTE:
For location of Data Link Connector (DLC), see DATA LINK CONNECTOR
. Manufacturer recommends using Scan Tool VAG 1551/1552 or VAS 5051/5052.
NOTE:
When voltage supply to ECM is interrupted, ECM looses all "learned" and/or "basic" values. Serious driveability problems may occur depending on vehicle mileage. A relearn procedure must be performed, see TEST DRIVE RELEARN PROCEDURE
.
NOTE:
This test should only be performed if engine performance is poor. Intake manifold switches from long intake path to short at approximately 4500 RPM. Intake Manifold Tuning (IMT) valve (N156) and actuator are located on right side of intake manifold. See Fig 1
.
- Verify battery voltage is a minimum of 11.5 volts and all fuses are okay. Repair as necessary. Start engine and let idle. Using a second technician, briefly depress accelerator pedal. Check for movement of vacuum actuated IMT linkage and shaft (shaft is located in intake manifold). See Fig 1 . Vacuum actuated IMT linkage and shaft should move, temporarily closing off long manifold runners. Turn engine off. If vacuum actuated IMT linkage and shaft function properly, IMT system is okay. If vacuum actuated IMT linkage and shaft do not operate properly, go to next step.
- Using a vacuum pump, check vacuum actuator, IMT linkage and shaft operation. If vacuum actuator, IMT linkage and shaft operate properly, go to next step. If vacuum actuator, IMT linkage and shaft do not operate properly, repair or replace as necessary. Verify repair. Test is complete.
- Turn ignition on. Using scan tool activate IMT valve. IMT valve should audibly click and actuator will operate if vacuum is present in vacuum reservoir. If IMT valve operation is okay, IMT system is okay. If IMT valve does not audibly click, go to next step.
- Disconnect IMT valve 2-pin harness connector. See Fig 1 . Using adapter cables from Test Kit (VAG 1594), connect Voltage Tester (VAG 1527) to IMT valve 2-pin harness connector. With ignition on, observe voltage tester LED. Voltage tester LED should blink (light to dark). Record results. If LED on voltage tester did not blink, go to next step. If voltage tester LED blinks, using scan tool, stop actuation of IMT valve. Turn ignition off. Replace faulty IMT valve. After repairs, erase DTC memory. Verify repair. Test is complete.
- Turn ignition on. Check for battery voltage at outgoing side of fuse No. 18. See Figure . If battery voltage is present, turn ignition off and go to next step. If battery voltage is not present, check power supply for fuse No. 18. See ENGINE PERFORMANCE in SYSTEM WIRING DIAGRAMS article in ELECTRICAL. Repair as necessary. After repairs, erase DTC memory. Verify repair. Test is complete.
- Disconnect ECM harness connector. Connect Test Box (VAG 1598/31) to ECM harness connector. See CONNECTING VAG TEST BOX . Using DVOM, check for continuity between IMT 2-pin harness connector terminal No. 2 and test box socket No. 104. See Fig 2 . Using DVOM, check for continuity between IMT valve 2-pin harness connector terminal No. 1 and fuse No. 18. Resistance should be a maximum of 1.5 ohms for each reading. If DVOM measurements are okay, replace faulty ECM. See ENGINE CONTROL MODULE under REMOVAL, OVERHAUL & INSTALLATION. After repairs, erase DTC memory. Verify repair. Test is complete. Perform ECM relearn procedure. See TEST DRIVE RELEARN PROCEDURE .