Intake Manifold Installation - Lower

WARNING: This page is about a different car, the 2003 Buick Century. However, it is still accessible from the selected car via links, so may be relevant.

IMPORTANT: All gasket-mating surfaces need to be free of oil, and foreign material. Use GM P/N 12346139 (Canadian P/N 10953463) or equivalent to clean surfaces.

Install the lower intake manifold gaskets.
With gaskets in place apply a small drop 8-10 mm (0.31-0.39 in) of RTV sealer GM P/N 12346286 (Canadian P/N 10953472) or equivalent to the 4 corners of the intake manifold to block joint (1).

Fig 1: Identifying Sealant Areas On Corners Of Intake Manifold
Courtesy of GENERAL MOTORS CORP.
Connect the 2 small drops with a bead of RTV sealer that is between 8-10 mm (0.31-0.39 in) wide and 3.0-5.0 mm (0.12-0.20 in) thick (2).
Install the lower intake manifold.
NOTE: Failure to tighten vertical bolts before the diagonal bolts may cause an oil leak.
Apply sealer GM P/N 12345382 (Canadian P/N 10953489) or the equivalent to the lower intake manifold bolt threads.
NOTE: Refer to FASTENER NOTICE in Cautions and Notices.
Install the lower intake manifold bolts.
Tighten See TSB For Revised Lower Intake Torque

Fig 2: View Of Lower Intake Manifold Bolt Tightening Sequence
Courtesy of GENERAL MOTORS CORP.
Install the heater inlet pipe.
Install the heater inlet pipe nut.
Tighten

Tighten the heater inlet pipe nut to 25 N.m (18 lb ft).

Fig 3: Installing Heater Inlet Pipe & Retaining Nut
Courtesy of GENERAL MOTORS CORP.

IMPORTANT: Do not press on the fuel pressure regulator valve when installing the fuel injector rail assembly.
Install the fuel injector rail assembly.
1. 9.1. Install the fuel injector O-rings using GM P/N 12345616 (Canadian P/N 993182) or the equivalent.
2. 9.2. Install the injector nozzles into the lower intake manifold injector bores.
3. 9.3. Press on the injector rail using the palms of both hands until the injectors are fully seated.
Install the fuel injector rail bolts.
Tighten

Tighten the fuel injector rail bolts to 10 N.m (89 lb in).

Fig 4: Installing Fuel Injector Rail Assembly & Bolts
Courtesy of GENERAL MOTORS CORP.
Install the fuel feed and return pipe retaining clip.

Fig 5: Installing Fuel Feed & Return Pipe Retaining Clip & Bolt
Courtesy of GENERAL MOTORS CORP.
Install the fuel feed and return pipe retaining clip bolt.
Tighten

Tighten the fuel feed and return pipe retaining clip bolt to 8 N.m (71 lb in).