Lexus 17111-31141 Intake Manifold

To remove the intake manifold, start by relieving the fuel system pressure and disconnecting the negative battery terminal. Remove the air intake duct, radiator, and cowl cover assembly. For 2009 and earlier models, remove the fuel rail and injectors, throttle linkage, and throttle body from the intake manifold. Label and detach the PCV and vacuum hoses connected to the rear of the intake manifold. Raise the vehicle and remove the manifold lower mounting bolts. From above, remove the intake manifold upper mounting nuts and bolts, along with the manifold, gasket, and manifold insulator. For 2010 and later models, remove the engine cover, disconnect vacuum hoses and ventilation tubes, and remove the throttle body from the intake manifold. Disconnect the fuel intake line from the fuel rail and disconnect the electrical connectors and harness mounting fasteners. Disconnect and remove the main harness connector from the intake manifold and tumble control valves. Apply battery voltage to the tumble control valve electrical connector to close the valve. Remove the intake manifold support bracket and disconnect the vacuum switching valve assembly electrical connector. Unscrew the intake manifold mounting fasteners and remove the manifold. To install, clean the mating surfaces and check for warpage. Press a new gasket into the grooves on the intake manifold and install it over the studs on the cylinder head. Tighten the manifold-to-cylinder head nuts or bolts in three or four equal steps. Install the remaining parts in reverse order and check for coolant and vacuum leaks.

Disconnect the battery's negative terminal cable, all hoses, and wiring from the throttle body. Label hoses for reassembly. Remove the throttle body bracket, upper intake manifold brace, and air intake tube. Disconnect all wiring and hoses from the manifold, remove the upper intake manifold. Check the gasket's condition, replace if needed. For lower intake manifold removal, remove the fuel rail and interfering brace. Discard old lower intake manifold gaskets, clean off old gasket material from the manifold and cylinder heads. Installation is the reverse of removal, use new gaskets and tighten bolts in a criss-cross pattern from the center outward.

Install the remaining parts in the reverse order of removal, using a new gasket between the lower intake manifold and the upper intake manifold.

Remove the air intake duct and resonator, then remove the cowl cover assembly.

The upper direct injection fuel rail must be removed before the lower intake manifold can be removed.