For 1990-2009 cars

### Removal Procedure

Caution: Ensure that the vehicle is properly supported and squarely positioned. To help avoid personal injury when a vehicle is on a hoist, provide additional support for the vehicle on the opposite end from which the components are being removed.

1. Raise vehicle squarely on a lift. Refer to lift instructions for positioning vehicle.
2. Loosen front exhaust pipe clamp at engine block bracket and slide clamp out of engagement with bracket.
3. Remove front exhaust pipe-to-exhaust manifold nuts, lower front exhaust pipe, remove gasket and discard.
4. Lower vehicle.
5. Remove the A/C compressor and the rear compressor bracket. Refer to "Engine Drive Belt and Accessories" section of this manual for A/C compressor removal procedures.
6. Disconnect oxygen sensor 1 harness connector.
7. Remove exhaust manifold attachment nuts.
8. Remove the exhaust manifold and gasket. Discard the gasket.
9. Inspect the exhaust manifold to front exhaust pipe flange for warpage. Refer to "SOHC or DOHC Cylinder Head" sections for specifications on exhaust manifold flange warpage.

Front Exhaust Pipe-to-Manifold Flange Warpage:

Standard: 0.7 mm (0.028 in) max.

Service Limit: 0.7 mm (0.028 in) max.

### Installation Procedure

1. Install new exhaust manifold gasket with smooth side toward the exhaust manifold.
2. Install the exhaust manifold and attachment nuts.
3. In sequence, torque the exhaust manifold attachment nuts. The center fasteners may lose torque when the outer fasteners are tightened. Therefore, re-torque all fasteners a second time.

Tighten
Tighten Exhaust Manifold-to-Head (L24) 22 N·m (16 lbs ft).

Tighten
Tighten Exhaust Manifold-to-Head (LL0) 17 N·m (13 lbs ft).

Important: Whenever the oxygen sensor 1 is removed, coat the threads with a nickel based anti-seize such as Saturn P/N 21485279 (or equivalent). If oxygen sensor 1 is replaced, do not apply anti-seize to the new sensor. New sensors have anti-seize pre-applied. Do not use an anti-seize that contains silicone.

4. Connect oxygen sensor 1 harness connector. Push in until a click is heard and pull back to ensure a positive engagement.

Tighten
Tighten Sensor - Oxygen-to-Exhaust Manifold 45 N·m (33 lbs ft).

5. Install A/C compressor rear bracket and A/C compressor. Refer to "Engine Drive Belt and Accessories Drive" section of this manual for A/C compressor installation.

Tighten
Tighten Front/Rear Brackets-to-Head/Block 25 N·m (19 lbs ft).

Tighten
Tighten Compressor-to-Front Bracket 54 N·m (40 lbs ft).

Tighten
Tighten Compressor-to-Rear Bracket 25 N·m (19 lbs ft).

6. Raise vehicle squarely on a lift. Refer to lift instructions for positioning vehicle.
7. Install new exhaust pipe-to-manifold gasket on the studs.
8. Install and torque the exhaust pipe-to-manifold attachment nuts.

Tighten
Tighten Exhaust Pipe-to-Manifold 31 N·m (23 lbs ft).

9. Slide front exhaust pipe clamp over engine block bracket and tighten clamp.

Tighten
Tighten Exhaust Pipe Clamp-to-Support Bracket 60 N·m (44 lbs ft).

10. Lower vehicle and check for leaks.