| • | Throttle body | 
| • | Intake manifold | 
| • | Intake manifold gasket sealing areas | 
| • | Intake manifold passages | 
| • | Brake booster hose passage | 
| • | Evaporative emission (EVAP) solenoid passage | 
| • | Positive crankcase ventilation (PCV) vacuum hose passages | 
| • | Barometric pressure (BARO) sensor passage | 
Caution: Refer to Safety Glasses Caution in the Preface section.
| • | Damage, debris or restrictions to the BARO sensor mounting port | 
| • | 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 communicator valve mounting bosses (1) | 
| • | Damage, debris or restrictions to the communicator valve port (2) | 
| • | Damage to the communicator valve components | 
| • | Gouges or damage to the upper intake manifold sealing surfaces (1) | 
| • | Damage to the gasket sealing surface (2) for the throttle body | 
| 5.1. | Locate a straight edge across the upper-to-lower intake manifold sealing surface. | 
| 5.2. | Insert a feeler gage between the upper intake manifold and the straight edge. An upper intake manifold with warpage in excess of 0.05 mm (0.020 in) must be replaced. | 
| • | Upper-to-lower intake manifold sealing surface | 
| • | Cylinder head-to-lower intake manifold sealing surface | 
| • | Intake manifold gasket sealing surfaces | 
| • | Intake manifold passages | 
Caution: Refer to Safety Glasses Caution in the Preface section.
| • | 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 | 
| 3.1. | Locate a straight edge across the lower intake manifold sealing surfaces. | 
| 3.2. | Insert a feeler gage between the lower intake manifold and the straight edge. A lower intake manifold with warpage in excess of 0.5 mm (0.020 in) must be replaced. |