Removal (GS430, LS430 & SC430)
WARNING: This page does not describe the selected car, but rather 8 other vehicles, including the 2003 Lexus SC 430, 2003 Lexus RX 300, 2003 Lexus LX 470, 2003 Lexus LS 430, and 2003 Lexus IS 300. However, it is still accessible from the selected car via links, so may be relevant.
Remove engine cover. Disconnect negative battery cable. Drain cooling system. Remove intake air connector pipe located between throttle body and air cleaner assembly. See Fig 1. Disconnect Throttle Position (TP) sensor connector. Disconnect throttle control motor connector. Disconnect water by-pass hoses from throttle body. Remove bolts/nuts and throttle body from intake manifold. Remove throttle body and gasket.