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2.2L Turbo

  1. Ensure engine is at normal operating temperature. Ensure all electrical accessories and cooling fan are off. Throttle valve must be in idle position. TDC sensor must be fully seated in transaxle.
  2. Disconnect wire from terminal No. 1 of ignition coil. Terminal identifications are located on coil. Remove crankcase breather hose and plug cylinder head openings. Crankcase vapors must vent to atmosphere. Remove cap from charcoal canister "T" fitting and vent to atmosphere. See Fig 1 .
  3. Remove cap from exhaust probe receptacle and connect CO meter. Ensure fit is snug to prevent exhaust leaks. Connect Engine Analyzer (VW 1367). Start engine. Ensure idle speed is within specification. See IDLE SPEED & CO LEVEL SPECIFICATIONS (2.2L TURBO)  table.
    NOTE: If injection lines are disconnected, increase engine speed to 3000 RPM several times, and then allow engine to idle for at least 2 minutes to bleed injectors and lines.
    IDLE SPEED & CO LEVEL SPECIFICATIONS (2.2L TURBO)

    Application Idle RPM % CO Level
    Man. Trans. 750-850 0.3-1.2
    Auto. Trans. 670-l770 0.3-1.2
    Fig 1: Identifying Breather Hose & "T" Fitting Locations
    G93049Courtesy of AUDI OF AMERICA, INC.
  4. Using Cable Adapter (US 1112), connect test lead to Blue/Black oxygen sensor test connector. Depress "0/0" (dwell angle) button on engine analyzer. Disregard RPM reading. With the oxygen sensor connected, check CO level. Refer to the IDLE SPEED & CO LEVEL SPECIFICATIONS (2.2L TURBO)  table. Oxygen sensor duty cycle must fluctuate between 25-65 percent.
  5. If CO reading is more than 1.2 percent with oxygen sensor duty cycle reading between 25-65 percent, check ignition system, exhaust system and fuel distributor for malfunction. If oxygen sensor duty cycle is NOT between 25-65 percent, check fuel system, ignition system and emission system and repair as necessary.
  6. If all systems are okay and CO is still not within specification, stop engine and remove air intake duct from airflow meter. Punch hole in center of CO adjusting screw plug and drill a 3/32 hole to a depth of 5/32". DO NOT  drill completely through as adjustment screw will be damaged.
  7. Install a 1/8" sheet metal screw and remove plug using pliers. Install air intake duct on airflow meter. Start and briefly increase engine speed to 2000 RPM. Return engine to idle.
    NOTE: DO NOT  accelerate engine with adjusting wrench in place. Remove wrench after each adjustment and accelerate engine briefly before measuring CO level.
  8. Using Adjustment Wrench (P 377), adjust oxygen sensor duty cycle until it fluctuates between 42-58 percent. Ensure idle speed is within specification. Turn engine off. Install new plug in mixture control unit. Remove all test equipment and connect all hoses and wiring.
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