How to Replace the Throttle Body in a Toyota Corolla

The Toyota Corolla is small, reliable, affordable and fuel-efficient. As a result, it is the best selling nameplate in the history of automotive sales. More than 200,000 Americans, including everyone from high schools kids to retirees, purchase Corollas every year. Used-vehicle buyers looks for the eighth-generation Corolla (1998 to 2002) because of its solid acceleration in a 1.8L engine, comfortable ride and outstanding quality and materials. The following steps detail the installation of a new throttle body in in the eighth-generation Corolla with the 1.8L engine.

Difficulty:

Challenging

Instructions

things you'll need:

• Mechanic's toolset, including a full socket set, wrenches and screwdrivers
• Torque wrench
• Clean shop cloths
• Replacement gasket

1. Install the Throttle Body

   • 1

     Remove the ground cable from the battery. Drain the coolant from the engine into a suitable container that can be securely sealed.

   • 2

     Loosen and remove the two nuts and the two clips that hold Cover Number Two on the cylinder head. Remove the head cover.

   • 3

     Disconnect the connector for the mass air flow meter and the VSV connector. Take off the two wire harness clamps and take the fuel vapor feed hoses Number 1 from the VSV and then disconnect fuel vapor feed hose Number 3.

   • 4

     Pull the ventilation hose Number 1 from the cylinder head cover. Release the clamp bolt on air cleaner hose Number 1. Take off the air cleaner cap and the air cleaner hose.

   • 5

     Disengage the throttle control motor connector, then pull the water by-pass hose Number 1 from the throttle body. Disconnect water by-pass hose Number 2.

   • 6

     Loosen the bolts that hold the throttle body in place then remove them along with the two nuts. Lift out the throttle body.

   • 7

     Place a clean shop cloth over the opening to the manifold when the throttle body is removed. This will prevent dirt and debris from falling into the engine.

   Remove the Throttle Body

   • 1

     Clean the gasket mating surfaces completely to remove any old gasket material, carbon deposits and dirt. Install the new throttle body with a new gasket. Secure the throttle body with the nuts and bolts.

   • 2

     Continue the installation by reconnecting all components in the reverse order of their removal. Reconnect the negative battery cable.

   • 3

     Refill the engine with the recommended type and mix of coolant to the proper level. Properly dispose of old coolant when new is used to fill the engine.

   • 4

     Start the engine and inspect all the connections for coolant leaks. Add more coolant as needed to attain the proper levels.