For 1990-2009 cars

### Removal Procedure

1. Open the hood.
2. Remove the lower engine cover and the right engine splash guard.
3. Lower the vehicle by its full height.
4. Remove the front toothed belt cover (top). Refer to 1401280 - Replace Front Toothed Belt Cover (Top) .
5. Remove the spark plugs. Refer to 1401340 - Spark Plugs, Remove and Install .
6. Detach the engine management wiring harness from intake manifold, cylinder head cover.

Unclip 2x from bracket.

7. Detach the coolant expansion tank closure cap.
8. Remove the oil dipstick.
9. Set up the crankshaft.

Move the crankshaft in the direction of the engine rotation to the 1st cylinder TDC position (mark 1).

10. Apply guidance marks.

Attach 3 markings (2) as an aid to one of the camshaft adjusters, each one offset by 90 degrees to the marking applied (1).

### Inspection Procedure

Important: Follow manufacturer instructions.

1. Calibrate the pressure loss tester.

Connect to the compressed air system.

2. Install the pressure loss tester.

| Important: Wheels must be in contact with the ground.

• | Engage 1st gear and apply the parking brake.

• | Screw the connecting piece into the spark plug thread of cylinder no. 1.

• | Apply compressed air to cylinder no. 1.

3. Pressure Loss, Check

• | Take pressure loss reading.

- | The maximum permissible pressure differential between cylinders is approx. 10 percent.

- | Maximum pressure loss of a cylinder is 25 percent.

• | Take note of any visible escape of compressed air.

• | Intake manifold, exhaust manifold, crankcase

• | Take note of any bubble formation in the coolant compensation tank.

4. Perform pressure loss test by analogy on cylinders 3, 4 and 2.

### Installation Procedure

1. Detach the pressure loss tester.

Unscrew the connection piece from the spark plug thread.

2. Put the vehicle in neutral.
3. Insert the oil dipstick.
4. Attach the coolant expansion tank closure cap.
5. Install the spark plugs. Refer to 1401340 - Spark Plugs, Remove and Install .
6. Attach the engine management wiring harness to the intake manifold.

Clip 2x in bracket.

7. Install the front toothed belt cover (top). Refer to 1401280 - Replace Front Toothed Belt Cover (Top) .
8. Raise the vehicle by its full height.
9. Install the lower engine cover and the right engine splash guard.
10. Lower the vehicle by its full height.
11. Close the hood.