For 1990-2009 cars only
- Install the intake manifold, fitting the plenum duct over the intake manifold duct.
- Loosely install the intake manifold bolts.
- Tighten the intake manifold bolts in sequence (1-10). Tighten the intake manifold bolts to 10 N·m (89 lb in).
- Tighten the plenum duct clamp (1) to the intake manifold and tighten to 2.75 N·m (24 lb in).
- Inspect the fuel injector O-rings. Ensure the fuel injector O-rings are not missing, mis-aligned or damaged. Replace the O-rings if necessary.
- Lubricate the intake manifold fuel injector bores with light mineral oil GM P/N 9981704, clean engine oil, or equivalent.
- Install the fuel rail with fuel injectors as an assembly.
- Install the fuel rail studs and tighten to 9 N·m (80 lb in).
- Install the fuel rail bracket nut to the fuel rail stud at the engine lift bracket on the water crossover. Tighten the fuel rail bracket nut to 10 N·m (89 lb in).
- Install the PCV dirty air tube to the PCV orifice in the right camshaft cover and to the intake manifold.
- Install the PCV fresh air feed tube to the camshaft cover and the water crossover.
- Install the brake booster hose to the vacuum fitting in the water crossover.
Caution: Refer to Fastener Caution in the Preface section.
