Using Scan Tool
Start and warm engine up to normal operating temperature. Shut engine off. Connect scan tool to DLC3. see scheme 19 Start engine. Following scan tool manufacturer's instructions, check ignition timing.
Without Scan Tool
- Remove intake manifold cover located on top of engine. Start and warm engine up to normal operating temperature. Shut engine off. Connect tachometer to DLC1. (Scheme 2)
- Connect timing light to lead wire at ignition coil electrical connector on top of driver's side valve cover at cylinder No. 1. (Scheme 3) Cylinder No. 1 is front cylinder on left side of engine when viewed from flywheel end of engine. see scheme 13
- Install Jumper Wire (SST 09843-18020) between terminals TC and E1 on DLC1 located near driver's side strut tower. see scheme 24 Apply parking brake. Place transmission in Neutral. Start engine and allow engine to idle.
- Check timing marks located on timing belt cover, near crankshaft pulley. Ensure base timing is 8-12 degrees BTDC at idle with transmission in Neutral, and with A/C and all accessories off. Shut engine off. Remove jumper wire, timing light and tachometer. Reinstall intake manifold cover.
Scheme 2
Scheme 3
- Remove intake manifold cover located on top of engine. Start and warm engine up to normal operating temperature. Shut engine off. Connect scan tool to DLC3. see scheme 19 Use scan tool to read engine RPM.
- Connect timing light to lead wire at ignition coil electrical connector on top of driver's side valve cover at cylinder No. 1. (Scheme 3) Cylinder No. 1 is front cylinder on left side of engine when viewed from flywheel end of engine. see scheme 13
- Apply parking brake. Place transmission in Neutral. Ensure idle speed is 700-800 RPM. Check timing marks located on timing belt cover, near crankshaft pulley. Ensure base timing is 8-12 degrees BTDC at idle with A/C and all accessories off. Shut engine off. Remove timing light and scan tool. Reinstall intake manifold cover.
- Remove intake manifold cover located on top of engine. Start and warm engine up to normal operating temperature. Shut engine off. Connect tachometer to DLC3. (Scheme 4)
- Connect timing light to lead wire at ignition coil electrical connector on top of driver's side valve cover at cylinder No. 1. (Scheme 3) Cylinder No. 1 is front cylinder on left side of engine when viewed from flywheel end of engine. see scheme 13
- Apply parking brake. Place transmission in Neutral. Start engine and maintain engine at 2500 RPM for 90 seconds and allow engine to idle. Ensure idle speed is 700-800 RPM. Install Jumper Wire (SST 09843-18040) between terminals TC and CG on DLC3. (Scheme 5)
- Use timing light to check timing marks located on timing belt cover, near crankshaft pulley. Ensure base timing is 8-12 degrees BTDC at idle with transmission in Neutral, and with A/C and all accessories off. Shut engine off. Remove timing light and scan tool. Reinstall intake manifold cover.
Scheme 4
Scheme 5
Preliminary Inspection
- Using vacuum pump, apply 15.7 Hg in. of vacuum to throttle opener. Perform STEP 1. (Scheme 6) Ensure clearance exists at tip of throttle opener and no clearance exists between throttle stop screws and throttle levers. Perform STEP 1. (Scheme 6)
- Note location of No. 1 and 2 throttle bodies on No. 1 intake air control valve. Perform STEP 2. (Scheme 6) With 15.7 Hg in. of vacuum still applied to throttle opener, check that about.0051" (.130 mm) clearance exists between close side adjusting screw and throttle lever on No. 1 throttle body, and about.0087" (.220 mm) clearance exists between open side adjusting screw and throttle lever on No. 1 throttle body. Perform STEP 3. (Scheme 6)
- Fully open throttle lever on No. 2 throttle body and measure clearance between close side adjusting screw and throttle lever on No. 1 throttle body. Perform STEP 4. (Scheme 6) Clearance between close side adjusting screw and throttle lever on No. 1 throttle body should be.0098-.0177" (.250-.450 mm). If all clearances are as specified, throttle body lever adjustment is not required. If any clearance is not as specified, throttle body lever adjustment procedure must be performed. Proceed to adjustment procedure.
Scheme 6
Testing TP Sensor
- Disconnect electrical connector from TP sensor. Note electrical terminals on TP sensor. (Scheme 7)- (Scheme 9).
- Using ohmmeter, check resistance between terminals VC and E2 on TP sensor. (Scheme 7)and (Scheme 9). Replace TP sensor if resistance is not within specification. See «THROTTLE POSITION SENSOR RESISTANCE (GS300, IS300, GS430, LS430 & LX470)»(ref-11537-S30017807892000111700000) table. THROTTLE POSITION SENSOR RESISTANCE (GS300, IS300, GS430, LS430 & LX470) Application Terminals Ohms @ 68°F (20°C) GS300 & IS300 VC & E2 (1) 1200-3200 GS430, LS430 & LX470 VC & E2 (1) 1250-2350 (1) Resistance at 68°F (20°C).
