55. Intake Manifold Clean and Inspect

Intake Manifold Cleaning and Inspection

Cleaning Procedure





1. Important: Do not use the intake manifold-to-cylinder head sealing gaskets again.

Remove the manifold absolute pressure (MAP) sensor (714) from the rear of the intake. The MAP sensor is to be reinstalled upon completion of the cleaning and inspection procedures.
2. Inspect the sealing grommet on the MAP sensor. The grommet should not be torn or damaged.





3. Remove and discard the intake manifold-to-cylinder head gaskets (514).





4. Remove the fuel rail with injectors.





5. Remove the throttle body and gasket.





6. Remove the evaporative emissions (EVAP) purge solenoid (708), bolt (710), and isolator (709).
7. Clean the intake manifold in solvent.
^ Clean the intake manifold gasket surfaces.
^ Clean the intake manifold internal passages.

8. Caution: Refer to Safety Glasses Caution in Service Precautions.

Dry the intake manifold with compressed air.

Inspection Procedure





1. Inspect the throttle body studs and threaded inserts for looseness or damaged threads.
2. Inspect the wire harness stud and threaded insert for looseness or damaged threads.





3. Inspect the fuel rail bolt inserts for looseness or damaged threads.
4. Inspect the intake manifold vacuum passages for debris or restrictions.





5. Inspect for damaged or broken vacuum fittings, damaged MAP sensor (714) mounting bore, or broken MAP sensor retaining tabs.
6. Inspect the composite intake manifold assembly for cracks or other damage. Inspect the areas between the intake runners.
7. Inspect all the gasket sealing surfaces for damage.
8. Install the MAP sensor.





9. Inspect the fuel injector bores for excessive scoring or damage.
10. Inspect the intake manifold cylinder head deck for warpage.
1. Locate a straight edge across the intake manifold cylinder head deck surface. Position the straight edge across a minimum of two runner port openings.
2. Insert a feeler gage between the intake manifold and the straight edge. A intake manifold with warpage in excess of 3 mm (0.118 in) over a 200 mm (7.87 in) area is warped and should be replaced.





11. Notice: Refer to Fastener Notice in Service Precautions.

Install the EVAP solenoid (708), bolt (710), and isolator (709).
Tighten the EVAP solenoid bolt to 10 Nm (89 inch lbs.).