OEM 2003 Toyota Corolla Throttle Body

2003 Toyota Corolla Parts Questions & Experts Answers

• Q: How to service and repair the throttle body assembly on 2003 Toyota Corolla?

  A: The first step to service or repair the throttle body assembly requires draining the coolant. The service requires removal of the cylinder head cover No. 2 through the detachment of two nuts and two clips. Proceed by disconnecting the MAF connector and VSV connector as well as the 3 vacuum hoses before loosening the air cleaner hose clamp to remove the air cleaner hose No. 1 and then unfasten the cap sub-assembly. The first step is removing air cleaner hose No. 1 and performing a separation of the accelerator control cable assembly. The throttle body assembly requires disconnected throttle position sensor connector then throttle body ISC valve assembly connector and PCV hose as well as 2 water by-pass hoses. The throttle body requires removal of 5 bolts and 2 nuts for Transaxle M/T while Transaxle A/T needs 3 bolts together with 2 nuts and two accelerator cable bracket bolts. The removal process starts with taking out the two screws securing the E.F.I. throttle position sensor and then continuing with unscrewing three screws of the throttle body idle speed control valve assembly while also removing its gasket. Apply new gasket material to the throttle body and fasten the idle speed control valve assembly with 3 screws at a torque rate of 3.7 N.m (38 kgf.cm, 33 in.lbf). Position the throttle position sensor counterclockwise between 30 degrees to 90 degrees with respect to the closed valve position while tightening 2 screws to 2.0 N.m (20 kgf.cm, 18 in.lbf). Secure the accelerator control bracket with 2 bolts torqued to 13 N.m (133 kgf.cm, 9.6 ft.lbf) then install the new gasket on the intake manifold followed by a mounting process of the throttle body with 5 bolts and 2 nuts (Transaxle M/T) torqued to 30 N.m (306 kgf.cm, 22 ft.lbf) and 13 N.m (133 kgf.cm, 9.6 ft.lbf) or with 3 bolts and 2 nuts (Transaxle A/T) at 30 N.m (306 kg The technician should join both water bypass hoses with the PCV hose as well as the throttle body idle speed control valve assembly connector and the throttle position sensor connector. The installation process includes placing the air cleaner cap sub-assembly with attachment of air cleaner hose followed by VSV connector and intake air flow meter connector and 3 vacuum hoses. The engine requires a final step to reattach the cylinder head cover No. 2 with 2 nuts fastened by 2 clips at a torque of 7.0 N.m (71 kgf.cm, 62 in.lbf). Afterward, add coolant and verify the engine remains leak-free.