Intake manifold — removal and installation
Warning: Wait until the engine is completely cool before beginning this procedure.
Upper intake manifold
Note: Toyota refers to the upper intake manifold as the intake air surge tank. If you’re buying a gasket for the upper intake manifold at a dealer parts department, use the Toyota terminology.
1. Disconnect the cable from the negative terminal of the battery (see Engine electrical systems).
Warning: If you plan on removing the lower intake manifold, relieve the fuel system pressure before disconnecting the battery (see Fuel pressure relief procedure).
2. Disconnect all hoses and the wiring from the throttle body (see Fuel and exhaust systems). The coolant hoses can be pinched off to avoid draining the cooling system. Label the hoses to avoid confusion later.
3. Disconnect the air intake tube from the throttle body.
4. Remove the throttle body bracket and the upper intake manifold brace.
5. Disconnect all wiring and hoses from the manifold.
6. Remove the intake manifold mounting fasteners and remove the upper intake manifold (see illustration).
5.6 Upper intake manifold fasteners
7. Check the condition of the upper intake manifold gasket (see illustration). If it isn’t cracked, hardened or flattened, it can be reused.
5.7 Check the condition of the upper intake manifold gasket, replacing it if necessary
8. Installation is the reverse of removal. Be sure to tighten the upper intake manifold mounting bolts and nuts to the torque listed in this Chapter’s Specifications.
Lower intake manifold
Note: Toyota refers to the lower intake manifold as simply the «intake manifold.» If you’re buying a gasket for the lower intake manifold at a dealer parts department, use the Toyota terminology.
9. Remove the upper intake manifold (see Steps 1 through 7).
10. If you’re removing the lower intake manifold to replace it, remove the fuel rail now (see Fuel and exhaust systems).
11. If you’re just removing the lower intake manifold to replace the gaskets, it’s not necessary to remove the fuel rail, but you’ll have to disconnect the fuel line connection (see Fuel and exhaust systems).
12. Remove the interfering brace.
13. Unscrew the bolts and remove the lower intake manifold (see illustration).
5.13 Lower intake manifold mounting bolts
14. Remove and discard the old lower intake manifold gaskets. Clean off all traces of old gasket material from the mating surfaces of the manifold and cylinder heads, then wipe the surfaces with brake system cleaner.
15. Installation is the reverse of removal. Be sure to use new gaskets and tighten the lower intake manifold bolts a little at a time, in a crisscross pattern working from the center bolts outward, to the torque listed in this Chapter’s Specifications.