Cylinder Head Assembly: Service and Repair

1. Disconnect battery ground cable.
2. Remove undercover, then drain engine coolant and engine oil.
3. Remove air cleaner assembly.
4. Disconnect accelerator cable and cruise control actuator cable, if equipped.
5. Disconnect heater hoses from cylinder head rear cover.
6. Disconnect vacuum hoses from throttle body.
7. On models equipped with cruise control, remove cruise control actuator.
8. On all models, remove washer reservoir, then the ignition coil.
9. Remove water outlet hose, brake booster vacuum hose and PCV hose.
10. Remove EGR valve and pipes.
11. Disconnect cold start injector electrical connector, then remove two injector pipe attaching bolts and injector pipe.
12. Remove fuel pipe, then the pressure regulator.
13. Disconnect water bypass hoses from auxiliary valve.
14. Remove vacuum pipe and cylinder head rear cover.
15. Mark and disconnect all necessary engine electrical connectors, then position wiring harness aside.
16. Remove distributor.
17. Disconnect exhaust pipe from exhaust manifold, then remove the manifold.
18. Remove delivery pipe and injectors as an assembly. Do not remove injection cover. Use caution not to drop injectors.
19. Remove vacuum tank.
20. Remove intake manifold and intake air control valve.
21. Remove accessory drive belts.
22. Remove cylinder head valve covers and gaskets, then the four spark plugs.
23. Remove water bypass, pipe and drive belt adjusting bar.
24. Remove righthand engine mounting insulator.
25. Remove water pump pulley.
26. Remove No. 2 and No. 3 timing belt covers and gaskets.
27. If timing belt is to be replaced, refer to TIMING BELT for procedure. If timing belt is to be reused, proceed as follows:
a. Turn crankshaft pulley and align groove with ``0'' mark on the No. 1 timing belt cover. Ensure all valve lifters on the No. 1 cylinder are loose. If not, turn crankshaft pulley one complete revolution.
b. Place alignment marks on the camshaft timing pulleys and belt.
c. Loosen idler pulley bolt, then push idler pulley as far left as possible and temporarily tighten it.
d. Remove timing belt from camshaft timing pulleys. Support timing belt so meshing of crankshaft timing pulley and timing belt does not shift.
e. Remove camshaft timing pulleys, then the No. 4 timing belt cover.

Fig. 1 Measuring Camshaft Thrust Clearance:

Fig. 2 Camshaft Bearing Cap Bolt Removal. 4A-GE:

Fig. 3 Cylinder Head Bolt Removal Sequence. 4A-GE:

Fig. 4 Cylinder Head Bolt Tightening Sequence. 4A-GE:

Fig. 5 Camshaft Bearing Cap Bolt Tightening Sequence. 4A-GE:

28. Measure camshaft thrust clearance, Fig. 1. If clearance is greater than .0118 inch, replace camshaft and/or cylinder head.
29. Loosen and remove camshaft bearing cap bolts gradually in sequence shown in Fig. 2, then the camshafts.
30. Loosen and remove cylinder head attaching bolts gradually in sequence shown in Fig. 3. Head warpage or cracking could result from removing cylinder head bolts in incorrect order.
31. Reverse procedure to install. Torque cylinder head attaching bolts gradually in three steps in sequence, Fig. 4, torque bolts to 22 ft. lbs., then an additional 90°, then another 90°.
32. Torque bearing cap attaching bolts gradually in three steps in sequence Fig. 5, to 9 ft. lbs.