Cylinder Head

REMOVAL & INSTALLATION

1. Before servicing the vehicle, refer to the precautions in the beginning of this section.
2. Properly relieve the fuel system pressure.
3. Remove or disconnect the following:
   • Negative battery cable
   • Oxygen (O2S) sensor. If equipped with California emissions, disconnect the rear O2S sensor.
   • Engine undercover
   • Exhaust Y-pipe and lower it just enough to clear the studs in the heads. Do not allow the Y-pipe to hang without support.
   • Accessory drive belts
   • Engine accessories and brackets from the side of the engine the cylinder head is being removed
   • Connector bracket attaching bolt, if necessary
4. On the left cylinder head, remove the CMP sensor.
5. Remove or disconnect the following:
   • Fuel pipes
   • Intake manifold and gasket
   • Timing belt, camshaft sprockets, and related components
   • Valve covers, camshafts and related components
   • Oil dipstick tube attaching bolt on the left cylinder head
   • Cylinder head bolts in the proper sequence. Leave bolts 1 and 3 installed loosely to prevent the cylinder head from falling.
6. Separate the cylinder head from the block. Use a plastic-faced hammer, if needed.
7. Remove bolts 1 and 3. Remove the cylinder head and gasket.
8. Clean all gasket material from both mating surfaces.

   Fig. 2: Cylinder head bolt loosening sequence

   To install:

9. Inspect the cylinder head for warpage. Warpage should not exceed 0.0020 in. (0.05mm).
10. Install the cylinder head(s) on the block using new gaskets. Secure in place with the mounting bolts. Coat each bolts with clean engine oil, and hand-tighten.

    Fig. 3: Cylinder head torque sequence-2.5L engine

11. Tighten the cylinder head bolts as follows:
    1. Step 1: Torque the bolt to 22 ft. lbs. (29 Nm)
    2. Step 2: Torque the bolt to 51 ft. lbs. (69 Nm)
    3. Step 3: Loosen all bolts by 180 degrees, then loosen an additional 180 degrees.
    4. Step 4: Bolts 1 and 2: 25 ft. lbs. (24 Nm)
    5. Step 5: Bolts 3, 4, 5 and 6: 11 ft. lbs. (15 Nm).
    6. Step 6: All bolts: turn an additional 80-90 degrees.
    7. Step 7: All bolts: turn an additional 80-90 degrees.

       WARNING
       Do not exceed 180 degrees total tightening.

12. Install or connect the following:
    • Oil dipstick tube attaching bolt on the left cylinder head
    • Valve covers, camshafts and related components
    • Camshaft sprocket, timing belt, and related components
    • Intake manifold. Torque the bolts to 21-25 ft. lbs. (28-34 Nm).
    • Fuel delivery pipes
13. On the left cylinder head, install the CMP sensor.
14. Install or connect the following:
    • Connector bracket attaching bolt
    • Spark plug wires
    • Engine accessories and brackets
    • Accessory drive belts
    • Exhaust Y-pipe. Torque the fasteners to 19-26 ft. lbs. (25-35 Nm).
    • Engine undercover
    • Front O2S and rear O2S, if removed.
    • Negative battery cable
15. Start the engine and allow it to reach operating temperature.
16. Check for leaks.