Engine Controls - On-Vehicle Adjustments: Other Lexus RX I

ENGINE MECHANICAL

Before performing any on-vehicle adjustments to fuel or ignition systems, ensure engine mechanical condition is okay.

VALVE CLEARANCE

Note. Check and adjust valves with engine cold.

Scheme 1

Scheme 2

Scheme 3

Scheme 4

Scheme 5

Scheme 6

1. Remove passenger's side front fender apron for access to crankshaft pulley. Drain cooling system. Remove intake manifold cover. (Scheme 1)
2. Air intake chamber must be removed for removal of valve covers. Remove air cleaner cap assembly and air filter. Disconnect necessary electrical connections, control cables, PCV hose, coolant hoses, ground cables and vacuum hoses for removal of air intake chamber. (Scheme 1) Remove data link connector No. 1 from end of air intake chamber.
3. Remove nuts and disconnect power steering pressure tube from No. 1 engine hanger. (Scheme 1) Remove bolts, No. 1 engine hanger and throttle body brace. (Scheme 1)
4. Remove bolts/nuts, air intake chamber and gasket. Disconnect electrical connectors at ignition coils. Remove bolts and ignition coils. Disconnect upper radiator hose from coolant outlet at front of engine, between cylinder heads.
5. Disconnect electrical connectors for removal of wiring assemblies located above valve covers. Remove bolts/nuts and wiring assemblies. Remove bolts, valve covers and gaskets.
6. Rotate crankshaft pulley clockwise (viewed from front of engine) so crankshaft pulley timing mark (groove) aligns with "0" mark on timing belt cover and cylinder No. 1 is at TDC on compression stroke. Cylinder No. 1 is front cylinder on right side of engine when viewed from flywheel end of engine. (Scheme 2)
7. Ensure cylinder No. 1 intake and exhaust valve lifters are loose. If valve lifters are not as described, rotate crankshaft clockwise one full revolution (360 degrees) and realign crankshaft pulley timing mark (groove) with "0" mark on timing belt cover.
8. Using feeler gauge, measure valve clearance between valve lifter and camshaft on intake valves on cylinders No. 1 and 6, and exhaust valves on cylinders No. 2 and 3. Perform STEP 1. (Scheme 2) Record valve clearance.
9. Rotate crankshaft pulley clockwise an additional 240 degrees (2/3 revolution). Measure valve clearance of intake valves on cylinders No. 2 and 3, and exhaust valves on cylinders No. 4 and 5. Perform STEP 2. (Scheme 2) Record valve clearance.
10. Rotate crankshaft pulley clockwise an additional 240 degrees (2/3 revolution). Measure valve clearance of intake valves on cylinders No. 4 and 5, and exhaust valves on cylinders No. 1 and 6. Perform STEP 3. (Scheme 2) Record valve clearance.
11. Ensure valve clearance is within specification. See «VALVE CLEARANCE SPECIFICATIONS (ES300)»(ref-2756-S10414811942000041300000) table. VALVE CLEARANCE SPECIFICATIONS (ES300) Application (1) In. (mm) Intake.006-.010 (.15-.25) Exhaust.010-.014 (.25-.35) (1) Adjust valve clearance with engine cold.
12. If valve clearance adjustment is required, rotate crankshaft pulley so camshaft lobe on valve to be adjusted is facing upward, away from valve lifter. Rotate valve lifter so notch area on valve lifter is at 90-degree angle to camshaft. This will place notch area perpendicular to camshaft.
13. Valve Clearance Adjuster (SST 09248-55040) is used to remove adjusting shim. Using SST "A" of valve clearance adjuster, press valve lifter downward. (Scheme 3) Install SST "B" between camshaft and valve lifter with side marked with "7" or "9" in the proper location, depending on cylinder application. (Scheme 3) Side marked with "7" should be used on front valves on cylinders No. 1 and 2 only. Side marked with "9" should be used on all except front valves on cylinders No. 1 and 2. Remove SST "A".
14. Using small screwdriver and magnet, remove adjusting shim. Using micrometer, measure and record thickness of removed adjusting shim. Using measured clearance and adjusting shim thickness, determine correct thickness of adjusting shim to be used. (Scheme 5)and (Scheme 6).
15. Install replacement adjusting shim with imprinted numbers on adjusting shim facing downward, toward valve lifter. Using SST "A", press downward on valve lifter and remove SST "B". Recheck valve clearance.
16. If spark plug tube gasket in valve cover requires replacement, bend gasket retaining tab upward. Pry spark plug tube gasket from valve cover. Use care not to scratch valve cover sealing surface.
17. Using hammer and proper sized bushing driver, tap spark plug tube gasket into valve cover until spark plug tube gasket is even with valve cover surface. Bend retaining tab downward. Coat spark plug tube gasket sealing area with grease.
18. Before installing valve covers and gaskets, apply sealant at specified areas on cylinder head. (Scheme 4) Install gasket and valve cover. Install and tighten valve cover bolts to specification. See «TORQUE SPECIFICATIONS»(ref-2756-S26607163002000041300000). To install remaining components, reverse removal procedure using NEW gaskets. Tighten bolts/nuts to specification. See «TORQUE SPECIFICATIONS»(ref-2756-S26607163002000041300000). Fill cooling system.

Scheme 7

Scheme 8

Scheme 9

Scheme 10

Scheme 11

1. Drain cooling system. Remove air intake pipe for access to intake air connector with throttle body. (Scheme 7) Disconnect necessary electrical connectors, control cables, hoses and engine wire clamps for removal of intake air connector with throttle body.
2. Note location of throttle body bracket. (Scheme 7) Remove throttle body bracket-to-cylinder head nuts. Remove intake air connector-to-air intake chamber bolts/nuts. Remove air intake connector with throttle body and gasket from air intake chamber.
3. Remove oil filler cap. Remove bolts and upper timing belt cover with gasket. Upper timing belt cover is located above timing belt. Disconnect electrical connectors from ignition coils, located above the spark plugs, in between the valve covers. Remove bolts and ignition coils with spark plug wires. Remove spark plugs.
4. Disconnect engine wiring harness for access to valve covers. Remove bolts/nuts, valve covers and gaskets.
5. Rotate crankshaft pulley clockwise so crankshaft pulley timing mark (groove) aligns with "0" mark on timing belt cover and cylinder No. 1 (front cylinder) is at TDC on compression stroke. Ensure timing marks on camshaft sprockets are aligned with timing marks on timing belt cover. (Scheme 8) If timing marks are not aligned, rotate crankshaft pulley clockwise one full revolution (360 degrees) and realign crankshaft pulley timing mark (groove) with "0" mark on timing belt cover.
6. Using feeler gauge, measure and record valve clearance of intake valves on cylinders No. 1, 2 and 4, and exhaust valves on cylinders No. 1, 3 and 5. Perform STEP 1. (Scheme 9)
7. Rotate crankshaft pulley clockwise one full revolution (360 degrees) and realign crankshaft pulley timing mark (groove) with "0" mark on timing belt cover. Using feeler gauge, measure and record valve clearance of intake valves on cylinders No. 3, 5 and 6, and exhaust valves on cylinders No. 2, 4 and 6. Perform STEP 2. (Scheme 9)
8. Ensure valve clearance is within specification. See «VALVE CLEARANCE SPECIFICATIONS (GS300 & SC300)»(ref-2756-S14873361632000041300000) table. VALVE CLEARANCE SPECIFICATIONS (GS300 & SC300) Application (1) In. (mm) Intake.006-.010 (.15-.25) Exhaust.010-.014 (.25-.35) (1) Adjust valve clearance with engine cold.
9. If valve clearance adjustment is required, rotate crankshaft pulley so camshaft lobe is facing upward on valve to be adjusted. Rotate valve lifter so notch area on valve lifter is at 90-degree angle to camshaft. This will place notch area perpendicular to camshaft.
10. Valve Clearance Adjuster (SST 09248-55040) is used for adjusting valve clearance. Press valve lifter downward using SST "A" of valve clearance adjuster. (Scheme 10) Install SST "B" between camshaft and valve lifter with side marked with No. 7 or No. 9 at designated position. (Scheme 10) Remove SST "A". NOTE: When adjusting valve clearance on intake valve on cylinder No. 1, it may be necessary to remove No. 2 camshaft bearing cap so SST "B" may be installed between camshaft and valve lifter.
11. Using small screwdriver and magnet, remove adjusting shim. Using micrometer, measure thickness of removed adjusting shim. Using measured clearance and adjusting shim thickness, determine correct thickness of adjusting shim to be used. (Scheme 5)and (Scheme 6).
12. Install proper adjusting shim with imprinted numbers on adjusting shim facing downward, toward valve lifter. Using SST "A", press downward on valve lifter and remove SST "B". Recheck valve clearance.
13. Install No. 2 camshaft bearing cap if removed. Tighten camshaft bearing cap bolts to specification. See «TORQUE SPECIFICATIONS»(ref-2756-S26607163002000041300000).
14. To install remaining components, reverse removal procedure using NEW gasket for air intake connector. Before installing valve covers and gaskets, apply sealant at specified areas on cylinder head. See. (Scheme 11). Tighten bolts/nuts to specification. See «TORQUE SPECIFICATIONS»(ref-2756-S26607163002000041300000). Fill cooling system.

Scheme 12

Scheme 13

Scheme 14

Scheme 15

1. Remove intake manifold cover located on top of engine, above intake manifold. Drain cooling system if any coolant hoses must be disconnected for access to valve covers. Remove air cleaner assembly (if necessary) and all necessary air intake hoses for access to valve covers.
2. On LS400, LX470 and SC400, remove bolts/nuts and upper timing belt cover from front of each cylinder head at each camshaft. On all models, disconnect electrical connector at each ignition coil. Remove bolts and ignition coils from valve covers.
3. Remove engine and transmission oil dipsticks (if necessary) for access to valve covers. Disconnect necessary hoses, hose brackets and engine wiring brackets for access to valve covers. Remove bolts, seal washers, valve covers and gaskets.
4. Rotate crankshaft pulley clockwise (viewed from front of engine) so crankshaft pulley timing mark (groove) aligns with "0" mark on lower timing belt cover and cylinder No. 1 is at TDC on compression stroke. Cylinder No. 1 is front cylinder on left side of engine when viewed from flywheel end of engine. (Scheme 12)
5. On GS400, ensure timing marks on back of camshaft sprockets are aligned. (Scheme 13) On LS400, LX470 and SC400, ensure timing marks on camshaft sprockets are aligned with timing marks on timing belt rear plate. (Scheme 14)and (Scheme 15). On all models, if timing marks are not aligned, rotate crankshaft clockwise one full revolution (360 degrees) and realign crankshaft pulley timing mark (groove) with "0" mark on timing belt cover.
6. Using feeler gauge, measure valve clearance between valve lifter and camshaft on intake valves on cylinders No. 1, 2, 5, 7 and 8, and exhaust valves on cylinders No. 1, 4 and 8. Perform STEP 1. (Scheme 12) Record valve clearance.
7. Rotate crankshaft pulley clockwise one full revolution (360 degrees). Using feeler gauge, measure valve clearance between valve lifter and camshaft on intake valves on cylinders No. 3, 4 and 6, and exhaust valves on cylinders No. 2, 3, 5, 6 and 7. Perform STEP 2. (Scheme 12) Record valve clearance.
8. Ensure valve clearance is within specification. See «VALVE CLEARANCE SPECIFICATIONS (GS400, LS400, LX470 & SC400)»(ref-2756-S09575244072000041300000) table. VALVE CLEARANCE SPECIFICATIONS (GS400, LS400, LX470 & SC400) Application (1) In. (mm) Intake.006-.010 (.15-.25) Exhaust.010-.014 (.25-.35) (1) Adjust valve clearance with engine cold.
9. If valve clearance adjustment is required, adjusting shim between valve lifter and valve stem must be changed. To remove valve lifter, remove timing belt and camshafts. See appropriate article in ENGINES.
10. Remove valve lifter and adjusting shim from valve. Using micrometer, measure thickness of adjusting shim removed. Using measured clearance and adjusting shim thickness, determine correct thickness of adjusting shim to be used. (Scheme 16)and (Scheme 17). Install adjusting shim, valve lifter, camshafts and timing belt. Recheck valve clearance.
11. If spark plug tube gasket in valve cover requires replacement, bend gasket retaining tab upward. Pry spark plug tube gasket from valve cover. Use care not to scratch valve cover sealing surface.
12. Using hammer and proper sized bushing driver, tap spark plug tube gasket into valve cover until spark plug tube gasket is even with valve cover surface. Bend retaining tab downward. Coat spark plug tube gasket sealing area with grease.
13. Before installing valve covers and gaskets, apply sealant at specified areas on cylinder head. (Scheme 18) Install gasket, valve cover, seal washers and valve cover bolts. Install and tighten valve cover bolts to specification in several steps. See «TORQUE SPECIFICATIONS»(ref-2756-S26607163002000041300000).
14. To install remaining components, reverse removal procedure. Tighten bolts/nuts to specification. See «TORQUE SPECIFICATIONS»(ref-2756-S26607163002000041300000). Fill cooling system if drained.

Scheme 16

Scheme 17

Scheme 18

Scheme 19

1. Outer cowl top panel must be removed. (Scheme 19) Remove windshield wiper arm nuts and windshield wiper arms assemblies. Place protective tape along bottom of windshield to protect windshield. Remove cowl top seal.
2. Remove driver's side and passenger's side ventilation louvers. (Scheme 19) Disconnect electrical connector for wiper motor. Remove bolts and wiper motor with wiper link assembly. Remove bolts and outer cowl top panel.
3. Remove suspension upper brace. Suspension upper brace fits between strut towers and is bolted to top of each strut tower.
4. Remove passenger's side front fender apron for access to crankshaft pulley. Drain cooling system. Remove intake manifold cover. (Scheme 1)
5. Air intake chamber must be removed for removal of valve covers. Remove air cleaner cap assembly and air filter. Disconnect necessary electrical connections, control cables, PCV hose, coolant hoses, ground cables and vacuum hoses for removal of air intake chamber. (Scheme 1)
6. Remove nuts and disconnect power steering pressure tube from No. 1 engine hanger. (Scheme 1) Remove bolts, No. 1 engine hanger and throttle body brace. (Scheme 1)
7. Remove bolts/nuts, air intake chamber and gasket. Disconnect electrical connectors at ignition coils. Remove bolts and ignition coils. Disconnect upper radiator hose from coolant outlet at front of engine, between cylinder heads.
8. Disconnect electrical connectors for removal of wiring assemblies located above valve covers. Remove bolts/nuts and wiring assemblies. Remove bolts, valve covers and gaskets.
9. Rotate crankshaft pulley clockwise (viewed from front of engine) so crankshaft pulley timing mark (groove) aligns with "0" mark on timing belt cover and cylinder No. 1 is at TDC on compression stroke. Cylinder No. 1 is front cylinder on right side of engine when viewed from flywheel end of engine. (Scheme 2)
10. Ensure cylinder No. 1 intake and exhaust valve lifters are loose. If valve lifters are not as described, rotate crankshaft clockwise one full revolution (360 degrees) and realign crankshaft pulley timing mark (groove) with "0" mark on timing belt cover.
11. Using feeler gauge, measure valve clearance between valve lifter and camshaft on intake valves on cylinders No. 1 and 6, and exhaust valves on cylinders No. 2 and 3. Perform STEP 1. (Scheme 2) Record valve clearance.
12. Rotate crankshaft pulley clockwise an additional 240 degrees (2/3 revolution). Measure valve clearance of intake valves on cylinders No. 2 and 3, and exhaust valves on cylinders No. 4 and 5. Perform STEP 2. (Scheme 2) Record valve clearance.
13. Rotate crankshaft pulley clockwise an additional 240 degrees (2/3 revolution). Measure valve clearance of intake valves on cylinders No. 4 and 5, and exhaust valves on cylinders No. 1 and 6. Perform STEP 3. (Scheme 2) Record valve clearance.
14. Ensure valve clearance is within specification. See «VALVE CLEARANCE SPECIFICATIONS (RX300)»(ref-2756-S31186177122000041300000) table. VALVE CLEARANCE SPECIFICATIONS (RX300) Application (1) In. (mm) Intake.006-.010 (.15-.25) Exhaust.010-.014 (.25-.35) (1) Adjust valve clearance with engine cold.
15. If valve clearance adjustment is required, rotate crankshaft pulley so camshaft lobe on valve to be adjusted is facing upward, away from valve lifter. Rotate valve lifter so notch area on valve lifter is at 90-degree angle to camshaft. This will place notch area perpendicular to camshaft.
16. Valve Clearance Adjuster (SST 09248-55040) is used to remove adjusting shim. Using SST "A" of valve clearance adjuster, press valve lifter downward. (Scheme 3) Install SST "B" between camshaft and valve lifter with side marked with "7" or "9" in the proper location, depending on cylinder application. (Scheme 3) Side marked with "7" should be used on front valves on cylinders No. 1 and 2 only. Side marked with "9" should be used on all except front valves on cylinders No. 1 and 2. Remove SST "A".
17. Using small screwdriver and magnet, remove adjusting shim. Using micrometer, measure and record thickness of removed adjusting shim. Using measured clearance and adjusting shim thickness, determine correct thickness of adjusting shim to be used. (Scheme 5)and (Scheme 6).
18. Install replacement adjusting shim with imprinted numbers on adjusting shim facing downward, toward valve lifter. Using SST "A", press downward on valve lifter and remove SST "B". Recheck valve clearance.
19. If spark plug tube gasket in valve cover requires replacement, bend gasket retaining tab upward. Pry spark plug tube gasket from valve cover. Use care not to scratch valve cover sealing surface.
20. Using hammer and proper sized bushing driver, tap spark plug tube gasket into valve cover until spark plug tube gasket is even with valve cover surface. Bend retaining tab downward. Coat spark plug tube gasket sealing area with grease.
21. Before installing valve covers and gaskets, apply sealant at specified areas on cylinder head. (Scheme 4) Install gasket and valve cover. Install and tighten valve cover bolts to specification. See «TORQUE SPECIFICATIONS»(ref-2756-S26607163002000041300000). To install remaining components, reverse removal procedure using NEW gaskets. Tighten bolts/nuts to specification. See «TORQUE SPECIFICATIONS»(ref-2756-S26607163002000041300000). Fill cooling system.

Scheme 20

Scheme 21

Scheme 22

1. Remove intake manifold cover. (Scheme 1) Start engine and warm engine to normal operating temperature. Shut engine off. Connect scan tool to data link connector No. 3. (Scheme 20) Scan tool is used to read engine RPM.
2. Connect timing light lead to Black/Red at ignition coil electrical connector on top of front valve cover at cylinder No. 4. (Scheme 21) Cylinder No. 4 is second cylinder on left side when viewed from flywheel end of engine. (Scheme 2)
3. Apply parking brake. Place transaxle in Neutral. Start engine and maintain engine at 2500 RPM for 90 seconds and allow engine to idle. Ensure idle speed is 650-750 RPM.
4. Install Jumper Wire (SST 09843-18020) between terminals TE1 and E1 on data link connector No. 1. (Scheme 22) Data link connector No. 1 is located on end of air intake chamber at passenger's side of engine compartment.
5. Timing marks are located on timing belt cover, near crankshaft pulley. Ensure base timing is 8-12 degrees BTDC at idle with transaxle in Neutral, and with A/C and all accessories off.
6. Remove jumper wire from data link connector No. 1. Ensure ECM controlled timing is 10-25 degrees BTDC. Shut engine off. Remove timing light and scan tool. Reinstall intake manifold cover.

Scheme 23

Scheme 24

Scheme 25

Scheme 26

Scheme 27

1. Start engine and warm engine to normal operating temperature. Shut engine off. Connect scan tool to data link connector No. 3. (Scheme 23) Scan tool is used to read engine RPM.
2. Connect timing light lead to White wire at ignitor. (Scheme 24)and (Scheme 25). Ignitor is located on top of driver's side strut tower.
3. 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 650-750 RPM.
4. Install Jumper Wire (SST 09843-18020) between terminals TC and E1 on data link connector No. 1. On GS300, data link connector No. 1 is located near driver's side strut tower. (Scheme 26) On SC300, data link connector No. 1 is located on end of air intake chamber. (Scheme 27)
5. On all models, timing marks are 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.
6. Remove jumper wire from data link connector No. 1. Ensure ECM controlled timing is 6-16 degrees BTDC. Shut engine off. Remove timing light and scan tool.

Scheme 28

Scheme 29

1. Remove intake manifold cover located on top of engine, above intake manifold. Start engine and warm engine to normal operating temperature. Shut engine off. Connect scan tool to data link connector No. 3. (Scheme 23) Scan tool is used to read engine RPM.
2. Connect timing light lead to Yellow wire at ignition coil electrical connector on top of driver's side valve cover at cylinder No. 1. (Scheme 28) Cylinder No. 1 is front cylinder on left side of engine when viewed from flywheel end of engine. (Scheme 12)
3. Install Jumper Wire (SST 09843-18020) between terminals TC and E1 on data link connector No. 1. (Scheme 29) Data link connector is located near driver's side strut tower. Apply parking brake. Place transmission in Neutral. Start engine and allow engine to idle.
4. Timing marks are 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 scan tool. Reinstall intake manifold cover.

Scheme 30

Scheme 31

1. Remove air cleaner inlet (if equipped) for access to intake manifold cover. Air cleaner inlet is located on top of the radiator. Remove intake manifold cover located on top of engine, above intake manifold. Start engine and warm engine to normal operating temperature. Shut engine off. Connect scan tool to data link connector No. 3. (Scheme 23) Scan tool is used to read engine RPM.
2. Connect timing light lead to Yellow wire at ignition coil electrical connector on top of driver's side valve cover at cylinder No. 1. (Scheme 30) Cylinder No. 1 is front cylinder on left side of engine when viewed from flywheel end of engine. (Scheme 12)
3. 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.
4. Install Jumper Wire (SST 09843-18020) between terminals TC and E1 on data link connector No. 1. (Scheme 31) Data link connector is located at near center of intake manifold and driver's side valve cover.
5. Timing marks are 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 scan tool. Reinstall intake manifold cover and air cleaner inlet.

LX470

1. Start engine and warm engine to normal operating temperature. Shut engine off. Remove intake manifold cover located on top of engine, above intake manifold. Connect scan tool to data link connector No. 3. (Scheme 23) Scan tool is used to read engine RPM.
2. Connect timing light lead to wire at ignition coil electrical connector on top of driver's side valve cover at cylinder No. 1. (Scheme 32) Cylinder No. 1 is front cylinder on left side of engine when viewed from flywheel end of engine. (Scheme 12)
3. Apply parking brake. Place transmission in Neutral. Start engine and maintain engine at 2500 RPM for 90 seconds and then allow engine to idle. Ensure idle speed is 650-750 RPM.
4. Install Jumper Wire (SST 09843-18020) between terminals TC and E1 on data link connector No. 1. (Scheme 33) Data link connector No. 1 is located on passenger's side front fender, behind air cleaner.
5. Timing marks are located on timing belt cover, near crankshaft pulley. Ensure base ignition timing is 5-15 degrees BTDC at idle with transmission in Neutral. Shut engine off. Remove jumper wire, timing light and scan tool. Reinstall intake manifold cover.

Scheme 32

Scheme 33

RX300

1. Remove intake manifold cover. (Scheme 1) Start engine and warm engine to normal operating temperature. Shut engine off. Connect scan tool to data link connector No. 3. (Scheme 34) Scan tool is used to read engine RPM.
2. Connect timing light lead to lead wire located near ignition on top of front valve cover. (Scheme 35) Apply parking brake. Place transaxle in Neutral. Start engine and maintain engine at 2500 RPM for 90 seconds and then allow engine to idle. Ensure idle speed is 650-750 RPM.
3. Install Jumper Wire (SST 09843-18020) between terminals TEI and E1 on data link connector No. 1. (Scheme 36) Data link connector No. 1 is located just in front of driver's side strut tower.
4. Timing marks are located on timing belt cover, near crankshaft pulley. Ensure base ignition timing is 8-12 degrees BTDC at idle with transaxle in Neutral, and with A/C and all accessories off. Remove jumper wire from data link connector No. 1. Ensure ECM controlled timing is 10-25 degrees BTDC. Shut engine off. Remove timing light and scan tool. Reinstall intake manifold cover.

Scheme 34

Scheme 35

Scheme 36

IDLE SPEED & MIXTURE

Note. Mixture adjustment is not possible on any model.

IDLE SPEED

Note. Idle speed is controlled by Engine Control Module (ECM) and is not adjustable. Check idle speed with air cleaner installed, all air induction system hoses and vacuum lines connected, electronic fuel injection system wiring connectors properly installed, transmission/transaxle in Neutral, ignition timing properly set, A/C and all accessories off, and engine at normal operating temperature.

ES300 & RX300

1. Start engine and warm engine to normal operating temperature. Shut engine off.
2. Connect scan tool to data link connector No. 3. (Scheme 20)or (Scheme 34). Scan tool is used to read engine RPM.
3. Apply parking brake. Place transaxle in Neutral. Start engine and maintain engine at 2500 RPM for 90 seconds and then allow engine to idle. Ensure idle speed is 650-750 RPM.
4. If idle speed is not within specification, check Idle Air Control (IAC) valve, wiring, Engine Control Module (ECM) and air intake system. See IDLE AIR CONTROL (IAC) SYSTEM in appropriate SYSTEM & COMPONENT TESTING article. Shut engine off. Remove scan tool.

GS300, GS400, LS400, LX470, SC300 & SC400

1. Start engine and warm engine to normal operating temperature. Shut engine off. Connect scan tool to data link connector No. 3. (Scheme 23) Scan tool is used to read engine RPM.
2. Apply parking brake. Place transmission in Neutral. Start engine and maintain engine at 2500 RPM for 90 seconds and then allow engine to idle. Ensure idle speed is within specification. See «IDLE SPEED SPECIFICATIONS»(ref-2756-S27981358492000041300000) table. IDLE SPEED SPECIFICATIONS Application Idle RPM GS300, LX470 & SC300 650-750 GS400, LS400 & SC400 700-800
3. If idle speed is not within specification, check air intake system for leaks. If air intake system is okay, check throttle body. See THROTTLE BODY under THROTTLE CONTROLS in appropriate SYSTEM & COMPONENT TESTING article. Shut engine off. Remove scan tool.

Note. Throttle body lever adjustment must be performed if throttle body or idle air control valve is replaced, or if throttle body or idle air control valve is removed and reinstalled. Perform preliminary inspection to determine if throttle body lever adjustment must be performed. Throttle stop screws and throttle opener are preset. DO NOT alter throttle stop screw or throttle opener adjustment.

Preliminary Inspection

1. Using vacuum pump, apply 15.7 Hg in. of vacuum to throttle opener. Perform STEP 1. (Scheme 37) Ensure clearance exists at tip throttle opener and no clearance exists between throttle stop screws and throttle levers. Perform STEP 1. (Scheme 37)
2. Note location of No. 1 and 2 throttle bodies on No. 1 intake air control valve. Perform STEP 2. (Scheme 37) 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 37)
3. Release vacuum and disconnect vacuum pump. 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 37) 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 37

Adjustment Procedure

1. Ensure preliminary inspection procedure is performed before performing adjustment procedure. Using vacuum pump, apply 15.7 Hg in. of vacuum to throttle opener.
2. To adjust open side adjusting screw, loosen lock nut on open side adjusting screw. (Scheme 38) Loosen open side adjusting screw to provide clearance between open side adjusting screw and throttle lever on No. 1 throttle body. Tighten open side adjusting screw until it just contacts throttle lever on No. 1 throttle body. DO NOT rotate open side adjusting screw after it just contacts throttle lever or throttle lever on No. 1 throttle body will not contact throttle stop screw and improper adjustment will exist. Loosen open side adjusting screw 1/4 turn and tighten lock nut.
3. To adjust close side adjusting screw, loosen lock nut on close side adjusting screw. (Scheme 38) Loosen close side adjusting screw to provide clearance between close side adjusting screw and throttle lever on No. 1 throttle body. Tighten close side adjusting screw until it just contacts throttle lever on No. 1 throttle body. DO NOT rotate close side adjusting screw after it just contacts throttle lever or throttle lever on No. 2 throttle body will not contact throttle stop screw and improper adjustment will exist. Loosen close side adjusting screw 1/2-3/4 turn and tighten lock nut.
4. After open and close side adjusting screws are adjusted, perform preliminary inspection procedure again to ensure proper throttle body lever adjustment.

Scheme 38

1. Manufacturer does not list procedure for Throttle Position (TP) sensor adjustment. Only information available is for checking resistance of TP sensor.
2. Disconnect electrical connector from TP sensor. Note electrical terminals on TP sensor. (Scheme 39) Apply vacuum to throttle opener.
3. Using ohmmeter, check resistance between specified terminals in relation to throttle position. See «THROTTLE POSITION SENSOR RESISTANCE (ES300 & RX300)»(ref-2756-S05020417782000041300000) table. Replace components as necessary if resistance is not within specification.

THROTTLE POSITION SENSOR RESISTANCE (ES300 & RX300) (1)

Scheme 39

Note. Manufacturer does not list procedure for Throttle Position (TP) sensor adjustment on the vehicle. Only information available is for checking resistance of TP sensor. Manufacturer lists adjustment procedure only when replacing TP sensor. Proper adjustment must be performed when installing TP sensor on throttle body. See THROTTLE BODY under FUEL SYSTEM in REMOVAL, OVERHAUL & INSTALLATION article.

1. Disconnect electrical connector from TP sensor. Note electrical terminals on TP sensor. (Scheme 40)and (Scheme 41).
2. Using ohmmeter, check resistance between terminals VC and E2 on TP sensor. (Scheme 40)and (Scheme 41). Replace TP sensor if resistance is not within specification. See «THROTTLE POSITION SENSOR RESISTANCE (GS300, GS400, LS400, LX470, SC300 & SC400)»(ref-2756-S40576183582000041300000) table. THROTTLE POSITION SENSOR RESISTANCE (GS300, GS400, LS400, LX470, SC300 & SC400) Application Terminals Ohms @ 68°F (20°C) GS300 & SC300 VC & E2 (1) 1200-3200 GS400, LS400, LX470 & SC400 VC & E2 (1) 1250-2350 (1) Resistance at 68°F (20°C).

Scheme 40

Scheme 41

Scheme 42

1. Start engine and warm engine to normal operating temperature. Shut engine off. Connect scan tool to data link connector No. 3. (Scheme 20) Scan tool is used to read engine RPM.
2. Apply parking brake. Place transaxle in Neutral. Start engine and maintain engine at 2500 RPM for 90 seconds and then allow engine to idle. Ensure idle speed is 650-750 RPM.
3. Shut engine off. Disconnect and plug vacuum hose at throttle opener near throttle body. (Scheme 42) Start engine and note engine speed. Engine speed should be 1100-1700 RPM.
4. If engine speed is not within specification, replace throttle body. Shut engine off. Reinstall vacuum hose on throttle opener. Start engine and ensure engine returns to proper idle speed.

1. Testing information is not available from manufacturer.

PARK/NEUTRAL POSITION (PNP) SWITCH

For adjustment of PNP switch, see PARK/NEUTRAL POSITION (PNP) SWITCH under ENGINE SENSORS & SWITCHES in REMOVAL, OVERHAUL & INSTALLATION article.

ES300

TORQUE SPECIFICATIONS (ES300)

GS300 & SC300

TORQUE SPECIFICATIONS (GS300 & SC300)

GS400, LS400, LX470 & SC400

TORQUE SPECIFICATIONS (GS400, LS400, LX470 & SC400)

TORQUE SPECIFICATIONS (RX300)