Catalytic Converter: Service and Repair

Removing And Installing Exhaust Manifold With Catalytic Converter

Technical values







Preliminary work
1. Remove air cleaner housing.
2. Open the oxygen sensor connectors in the engine compartment and expose the cables.
3. Remove oxygen sensors on the exhaust manifold.

Removal

Removing exhaust manifold

CAUTION:
Hot components
- Risk of burns

- Let hot components cool down.
- Wear personal protective gear.

Component overview







1. Unscrew three M8 lock nuts -1- on the three-hole flange for the front silencer.







1.1 The nuts must be replaced.

2. Unscrew nine M8 x 21 external Torx fastening screws -2- and remove exhaust manifold.










2.1. Remove and dispose of metal seal. The seal must be replaced.

Repair solution - replacing threaded bolts on three-hole flange







1. Tap out damaged threaded bolts on the exhaust manifold with a hammer.
2. Use M8 x 30 screw (Part No. 900.075.365.02) instead of the threaded bolt.

Installation

Installing exhaust manifold







1. Fit exhaust manifold with new metal seal and new lock nuts -1- on the three-hole flange for the front silencer.
2. Fit exhaust manifold with new metal seal and nine screws on the cylinder head flange.







2.1. The tab of the seal -arrow- must be facing the cylinder head.










2.2. Fit M8 x 21 screws -2- evenly at first according to the specified tightening sequence.
2.3. Tighten screws to the prescribed torque and according to the specified tightening sequence.

3. Tighten new M8 lock nuts on the three-hole flange.

Tightening specifications







1. First fit screws on the cylinder head and tighten according to the specified tightening sequence.
- Tightening torque: 23 Nm (17 ftlb.)







1.1 Then tighten new M8 lock nuts -1- on the three-hole flange.
- Tightening torque: 23 Nm (17 ftlb.)

Subsequent work
1. Fit oxygen sensor connectors in the engine compartment.
2. Install air cleaner housing.