Chevrolet Silverado / GMC Sierra. Service manual — part 176

Fig. 587: Upper Intake Manifold Damage
Courtesy of GENERAL MOTORS CORP.

5. Inspect the upper intake manifold for the following:

Cracks or other damage to the exterior (1)

Cracking or damage in the gasket grooves (2) and (3)

Damage to the throttle body mounting surface (4)

Loose or damaged bolt hole thread inserts (5)

2008 Chevrolet Silverado 1500

2008 ENGINE Engine Mechanical - 4.3L - Sierra & Silverado

Fig. 588: Lower Intake Manifold Damage
Courtesy of GENERAL MOTORS CORP.

6. Inspect the lower intake manifold for the following:

Damage to the gasket sealing surfaces (1) and (2)

Restricted cooling system passages (3)

Cracks or damage

Damage to the threaded bolt holes

INTAKE MANIFOLD ASSEMBLE

2008 Chevrolet Silverado 1500

2008 ENGINE Engine Mechanical - 4.3L - Sierra & Silverado

Fig. 589: Injectors At Lower Intake Manifold Bores
Courtesy of GENERAL MOTORS CORP.

IMPORTANT: During the removal of the fuel injector assembly, the

retainers that hold the injectors into the intake manifold may
become worn. This is OK. Upon installation of the upper
intake manifold, the injectors will be held fully seated, thus
keeping them from backing out of the lower intake manifold.

2008 Chevrolet Silverado 1500

2008 ENGINE Engine Mechanical - 4.3L - Sierra & Silverado

1. If reusing the fastener, apply threadlock GM P/N 12345382 (Canadian P/N 10953489) or

equivalent, to the threads of the fuel meter body bracket bolt.

2. Install the fuel meter body bracket and bolt.

Tighten: Tighten the fuel meter bracket bolt to 10 N.m (89 lb in).

3. Install the fuel meter body into the fuel meter body bracket.

4. Install the 6 injectors into the proper lower intake manifold bores in proper sequence (3, 5,

1, 2, 4, 6).

5. Inspect the injectors in order to ensure that they are firmly seated and locked in the lower

intake manifold bores.

6. Ensure that the electrical connections of the injectors are positioned so that they do not

interfere with each other, and are pointing towards the center of the intake manifold. Rotate
the electrical connector inboard if necessary. Also, ensure there is no tension on the injector
wires.

NOTE:

Refer to Fastener Notice .

IMPORTANT: All injector lines must face forward as the fuel meter body is

snapped into the bracket. Also, the number 3 fuel tube must
be positioned behind the number 1 fuel tube to eliminate
interference with the upper intake manifold when installed.

2008 Chevrolet Silverado 1500

2008 ENGINE Engine Mechanical - 4.3L - Sierra & Silverado