Important: This engine uses a sequential multiport fuel injection system. Injector wiring harness connectors must be connected to their appropriate fuel injector or exhaust emissions and engine performance may be seriously affected.
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.
Notice: Refer to Fastener Notice in the Preface section.
Important: All lower intake manifold bolts need to be cleaned and free of any foreign material, only new bolts are to be used.
Important: Manufacturer recommends the center bolts be fully torqued before the diagonal bolts to assure proper seal ability.
Important: Lower intake manifold bolts in location 6 and 7 should be torqued to specification using a crows foot type tool.
Install NEW lower intake manifold bolts.
Tighten
Tighten
Tighten the heater inlet pipe nut to 25 N·m (18 lb ft).
Tighten
Tighten the engine coolant temperature (ECT) sensor to 23 N·m (17 lb ft).
Important: Do not press on the fuel pressure regulator valve when installing the fuel injector rail assembly.
| 17.1. | Install the fuel injector O-ring using GM P/N 12345616 (Canadian P/N 993182), or equivalent. |
| 17.2. | Install the injector nozzles into the lower intake manifold injector bores. |
| 17.3. | Press on the injector rail using the palms of both hands until the injectors are fully seated. |
Tighten
Tighten the injector rail bolts to 10 N·m (89 lb in).
Tighten
Tighten the fuel feed and return pipe retaining clip bolt to 8 N·m (71 lb in).