Upper Intake Manifold Cleaning Procedure
- Remove any remaining gasket and/or gasket material from the following:
- Clean the following intake manifold areas in solvent.
• | Intake manifold gasket sealing areas. |
• | Intake manifold passages. |
• | Brake booster hose passage. |
• | Evaporative emission (EVAP) solenoid passage. |
• | Positive Crankcase Ventilation (PCV) vacuum hose passages. |
Caution: Refer to Safety Glasses Caution in the Preface section.
- Dry the upper intake manifold and throttle body with compressed air.
Inspection Procedure
- Inspect the upper intake manifold for the following conditions:
• | Damage, debris or restrictions to the brake vacuum booster hose port. |
• | Damage to the throttle body bolt holes. |
• | Damage, debris or restrictions to the PCV system hose ports. |
• | Damage to the intake manifold bolt bosses. |
• | Damage to the EVAP purge solenoid mounting boss. |
• | Damage, debris or restrictions to the EVAP purge solenoid port. |
• | Damage, debris or restrictions in the vacuum passage. |
• | Damage to the intake manifold runner control flap mounting bosses. |
• | Damage, debris or restrictions to the intake manifold runner control flap
port. |
• | Damage to the intake manifold runner control flap components. |
• | Gouges or damage to the upper intake manifold sealing surfaces. |
• | Damage to the gasket sealing surface for the throttle body. |
- Inspect the upper intake manifold sealing surface for warpage.
2.1. | Locate a straight edge (1) across the upper-to-lower intake manifold
sealing surface (3). |
2.2. | Insert a feeler gauge (2) between the upper-to-lower intake manifold
sealing surface (3) and the straight edge (1). An upper intake manifold
with warpage in excess of 0.05 mm (0.020 in) must be replaced. |
- Repair or replace the upper intake manifold as necessary.
Lower Intake Manifold Cleaning Procedure
- Remove any remaining gasket and/or gasket material from the following:
• | Upper-to-lower intake manifold sealing surface. |
• | Cylinder head-to-lower intake manifold sealing surface. |
- Clean the following intake manifold areas in solvent.
• | Intake manifold gasket sealing surfaces. |
• | Intake manifold passages. |
Caution: Refer to Safety Glasses Caution in the Preface section.
- Dry the intake manifold with compressed air.
Inspection Procedure
- Inspect the lower intake manifold for the following conditions:
• | Damage, debris or restrictions to the lower intake manifold ports |
• | Damage to the fuel rail mounting bolt holes |
• | Damage to the fuel rail |
• | Gouges or damage to the intake manifold sealing surfaces |
• | Damage to the lower intake manifold bolt bosses |
• | Damage to the fuel injector ports |
- Inspect the lower intake manifold sealing surfaces for warpage.
2.1. | Locate a straight edge (1) across the lower intake manifold sealing
surfaces (2). |
2.2. | Insert a feeler gauge (3) between the lower intake manifold sealing
surfaces (2) and the straight edge (1). A lower intake manifold with
warpage in excess of 0.5 mm (0.020 in) must be replaced. |
- Repair or replace the lower intake manifold as necessary.