Misfire Recognition: 4.2L
- Turn ignition off. Connect scan tool to Data Link Connector (DLC). DLC is located under cover on left side of instrument panel. See COMPONENT LOCATIONS
. Start engine. On scan tool, press "01" to select address word 01 - ENGINE ELECTRONICS. Press "Q" button to confirm input. Press "08" to select diagnostic function 08 - READ MEASURING VALUE BLOCK. Press "Q" button to confirm input, and go to next step.
- On scan tool, press "014" to select DISPLAY GROUP 014. Observe misfire recognition in display field No. 3. See Fig 1
. If displayed value is more than 5, go to next step. If displayed value is less than 5, go to step 4
.
Courtesy of AUDI OF AMERICA, INC.
- If displayed value is 0-5, perform following tests:
- Check spark plugs.
- Check spark plug connector between ignition coil and spark plug. Check for cracks or tears in connector.
- Check ignition coil and power output stage. For diagnostic procedure, see ignition coil related DTCs under DIAGNOSTIC TROUBLE CODE DEFINITIONS in appropriate SELF-DIAGNOSTICS article.
- Check fuel injectors. See FUEL INJECTOR TEST
under FUEL SYSTEM.
If problem is found, repair or replace as necessary. After repair go to next step.
- Using scan tool, clear DTCs and generate a ECM readiness code. See FUNCTION 05 - CLEARING DIAGNOSTIC TROUBLE CODES and READINESS CODE under SELF-DIAGNOSTIC SYSTEM in appropriate SELF-DIAGNOSTICS article. Test drive vehicle. Using scan tool, retrieve DTCs. If DTC does not reset, testing is complete.