Adjustments Audi 200 C3 рестайлинг

ENGINE COMPRESSION

Check compression with engine warm, all spark plugs removed and throttle wide open. Crank engine at least 6 strokes per cylinder.

Note. Connect coil high tension wire to ground before cranking engine for compression test.

4-CYLINDER COMPRESSION SPECIFICATIONS

5-CYLINDER COMPRESSION SPECIFICATIONS

VALVE CLEARANCE

Engine is equipped with hydraulic valve lifters. No adjustment is necessary.

Note. If lifters are replaced, DO NOT start engine for 30 minutes as valves may hit pistons. Lifters must be allowed to bleed down before starting engine.

IGNITION TIMING

Ignition timing, idle speed, and idle mixture are closely interelated and MUST be checked/adjusted together. Refer to IDLE SPEED & MIXTURE in this article.

4-CYLINDER IGNITION TIMING

5-CYLINDER IGNITION TIMING

IDLE SPEED & MIXTURE

Note. Mixture adjustment is NOT a part of normal tune-up procedure and should not be performed unless mixture control unit is replaced or vehicle fails emissions testing.

4-CYLINDER

Note. Fault codes of CIS-Motronic computerized engine control system MUST be checked before checking engine settings. If NO fault codes are stored, ignition timing, idle speed, and idle mixture may be checked/adjusted. Idle speed is electronically controlled and is NOT adjustable.

Scheme 1

1. Ensure engine is at normal operating temperature. Check that all electrical accessories and cooling fan are off. Increase engine speed to 3000 RPM, and then allow engine to idle for at least 2 minutes. Turn ignition off.
2. Using Test Adapter (VW 1363/3), connect CO tester to measuring tube. Connect Multimeter (US 1119) with Test Adapter (VW 1315A/1) to differential pressure regulator. (Scheme 1)
3. Turn ignition on. Control current must be positive. If not, reverse test probes. Remove crankcase housing breather hose and vent to atmosphere. Remove sealing cap from top of charcoal canister.
4. Connect timing light and check ignition timing. If necessary, remove tamper proof seal covering distributor clamp bolt and adjust ignition timing. After adjusting ignition timing, tigthen bolt and install a new tamper proof seal.
5. Check idle speed. If incorrect, check air intake system for leaks. If necessary, check/adjust airflow sensor potentiometer. If idle speed is correct, turn A/C system on (if equipped). Idle speed must increase by 70 RPM. If not, check CIS-Motronic computerized engine control system.
6. Check CO content by reading milliamp (mA) output on multimeter. Reading must fluctuate between zero and 5 milliamps. If reading is incorrect or it does not fluctuate, check oxygen sensor control system.
7. Read CO value on CO tester. Reading must be.2-1.2 percent by volume. If CO content is outside range, adjust idle mixture. Turn ignition off and remove rubber boot from mixture control unit.
8. Center punch hole in CO adjusting hole and drill a 3/32" hole to a depth of 5/32". DO NOT drill completely through as adjustment screw will be damaged. Install a 1/8" sheet metal screw and remove plug using pliers.
9. Install rubber boot on mixture control unit. Start and run engine at idle. Using Adjustment Wrench (P 377), turn adjustment screw clockwise or counterclockwise to adjust CO. (Scheme 2) Install new plug in mixture control unit.

Note. DO NOT push down on adjustment screw and do not accelerate engine with adjustment wrench in place. Remove wrench after each adjustment and accelerate engine briefly before measuring CO.

Scheme 2

4-CYLINDER IDLE SPEED & CO LEVEL SPECIFICATIONS

Scheme 3

1. Ensure engine is at normal operating temperature. Check that all electrical accessories and cooling fan are off. Throttle valve must be in idle position, and coolant switches must not be defective. TDC sensor must be fully seated in transaxle.
2. Disconnect wire from terminal No. 1 of ignition 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. (Scheme 3)
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, and adjust idle speed. NOTE: If injection lines were disconnected or replaced, increase engine speed to 3000 RPM several times, and then allow engine to idle for at least 2 minutes to bleed injectors and lines.
4. Using Cable Adapter (US 1112), connect test lead to Blue/Black oxygen sensor test connector. Depress "%" (dwell angle) button on engine analyzer. Disregard RPM reading. With oxygen sensor connected, CO value must be as specified. Oxygen sensor duty cycle must fluctuate between 25 percent and 65 percent.
5. If CO reading exceeds 1.2 percent with oxygen sensor duty cycle reading of 25-65 percent, check ignition system, exhaust system and fuel distributor. If oxygen sensor duty cycle is less than 25 percent, or greater than 65 percent, then CO adjustment is necessary.
6. Stop engine and remove air intake duct from airflow meter. Center punch hole in 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, then allow it to return to idle.
8. Using Adjustment Wrench (P 377), adjust oxygen sensor duty cycle until it fluctuates between 42 percent and 58 percent. Check idle speed and adjust if necessary. Turn engine off. Install new plug in mixture control unit. Remove all test equipment and connect all hoses and wiring. NOTE: DO NOT push down on adjustment screw and do not accelerate engine with adjusting wrench in place. Remove wrench after each adjustment and accelerate engine briefly before measuring CO.

2.3L Engine

1. Ensure engine is at normal operating temperature. Check that all electrical accessories and cooling fan are off. Turn ignition off. Remove cap from exhaust probe receptacle and connect CO meter. Ensure fit is snug to prevent exhaust leaks.
2. On 5000 series, remove vent hose from elbow at intake air boot. (Scheme 2) Leave elbow unplugged to draw fresh air through opening. Remove crankcase breather hose and plug cylinder head openings. Crankcase vapors must vent to atmosphere.
3. On 80/90 series, remove sealing cap from top of charcoal canister. Remove crankcase housing breather hose and vent to atmosphere. Crankcase vapors must vent to atmosphere.
4. On all models, connect Multimeter (US 1119) with Test Adapter (VW 1315A/1) to differential pressure regulator. Set scale to 200 milliamp (mA) DC. Start and warm engine to normal operating temperature. NOTE: If injection lines were disconnected or replaced, increase engine speed to 3000 RPM several times, and then allow engine to idle for at least 2 minutes to bleed injectors and lines.
5. Insert fuse in fuel pump relay. Malfunction indicator light must come on to indicate that ignition is stabilized for testing. Connect timing light and check ignition timing.
6. If timing is incorrect, loosen distributor clamp bolt and turn distributor. Remove fuse from fuel pump relay, increase engine speed above 2500 RPM, an allow engine to return to idle. Ignition timing MUST fluctuate between 7 and 20 degrees. Tighten distributor clamp bolt. NOTE: Some vehicles are equipped with a malfunction indicator light that comes on whenever an emission related fault occurs. Fuse from fuel pump relay must be removed and engine speed increased above 2500 RPM to cancel fault display.
7. Check idle speed. Idle RPM must be within specification. If not, check air intake system for leaks. Idle speed is electronically controlled and is NOT adjustable.
8. If necessary, check differential pressure regulator current with oxygen sensor connected. Reading must fluctuate between MINUS 4 mA to PLUS 6 mA and CO level must be.3-1.2 percent by volume. NOTE: On A/C equipped 80/90 models, turn A/C system on. If idle speed drops severly, check idle stabilization system.
9. Disconnect oxygen sensor harness and check CO content. Reading must be.3-3.0 percent by volume. If CO content is outside range, adjust idle mixture. Turn ignition off. Remove rubber boot from mixture control unit.
10. Center punch hole in CO adjusting hole and drill a 3/32" hole to a depth of 5/32". DO NOT drill completely through as adjustment screw will be damaged. Install a 1/8" sheet metal screw and remove plug using pliers.
11. Install rubber boot on mixture control unit. Start and run engine at idle. Using Adjustment Wrench (P 377), turn adjustment screw clockwise or counterclockwise to adjust CO reading. (Scheme 2) Install new plug in mixture control unit.

Note. DO NOT push down on adjustment screw and do not accelerate engine with adjusting wrench in place. Remove wrench after each adjustment and accelerate engine briefly before measuring CO.

5-CYLINDER IDLE SPEED & CO LEVEL SPECIFICATIONS

See also:
• IDLE SPEED & MIXTURE