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.
ES300 & RX300
Note. On RX300 models, start at step 1 . On ES300 models, start at step 2 .
Scheme 12
Scheme 13
Scheme 14
Scheme 15
- On RX300 models, remove outer cowl top panel. (Scheme 12) Remove windshield wiper arm nuts and windshield wiper arms assemblies. Place protective tape along bottom of windshield to protect windshield. Remove cowl top seal. Remove driver's side and passenger's side ventilation louvers. Disconnect electrical connector for wiper motor. Remove bolts and wiper motor with wiper link assembly. Remove bolts and outer cowl top panel. Remove suspension upper brace. Suspension upper brace fits between strut towers and is bolted to top of each strut tower.
- On all models, remove passenger's side front fender apron for access to crankshaft pulley. Drain cooling system. Remove intake manifold cover. (Scheme 13)
- 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 13) Remove data link connector (DLC) No. 1 from end of air intake chamber.
- Remove nuts and disconnect power steering pressure tube from No. 1 engine hanger. (Scheme 13) Remove bolts, No. 1 engine hanger and throttle body brace. (Scheme 13)
- 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.
- Disconnect electrical connectors for removal of wiring assemblies located above valve covers. Remove bolts/nuts and wiring assemblies. Remove bolts, valve covers and gaskets.
- 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 14)
- 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.
- 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 14) Record valve clearance.
- 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 14) Record valve clearance.
- 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 14) Record valve clearance.
- Ensure valve clearance is within specification. See «VALVE CLEARANCE SPECIFICATIONS (ES300 & RX300)»(ref-134931-S35733584582002022100000) table. VALVE CLEARANCE SPECIFICATIONS (ES300 & RX300) Application (1) In. (mm) Intake.006-.010 (.15-.25) Exhaust.010-.014 (.25-.35) (1) Adjust valve clearance with engine cold.
- 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.
- Valve Clearance Adjuster (SST 09248-55040) is used to remove adjusting shim. Using SST "A" of valve clearance adjuster, press valve lifter downward. (Scheme 15) Install SST "B" between camshaft and valve lifter with side marked with "7" or "9" in the proper location, depending on cylinder application. (Scheme 15) 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".
- 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 17)and (Scheme 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.
- 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.
- 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.
- Before installing valve covers and gaskets, apply sealant at specified areas on cylinder head. (Scheme 16) Install gasket and valve cover. Install and tighten valve cover bolts to specification. See «TORQUE SPECIFICATIONS»(ref-134931-S14922654382002022100000). To install remaining components, reverse removal procedure using NEW gaskets. Tighten bolts/nuts to specification. See «TORQUE SPECIFICATIONS»(ref-134931-S14922654382002022100000). Fill cooling system.
Scheme 16
Scheme 17
Scheme 18
Scheme 19
Scheme 20
Scheme 21
Scheme 22
Scheme 23
- Drain cooling system. Remove air intake pipe for access to intake air connector with throttle body. (Scheme 19) Disconnect necessary electrical connectors, control cables, hoses and engine wire clamps for removal of intake air connector with throttle body.
- Note location of throttle body bracket. (Scheme 19) 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.
- Remove oil filler cap. Remove bolts and upper timing belt cover with gasket. 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.
- Disconnect engine wiring harness for access to valve covers. Remove bolts/nuts, valve covers and gaskets.
- 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 20) 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.
- 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 21)
- 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 21)
- Ensure valve clearance is within specification. See «VALVE CLEARANCE SPECIFICATIONS (GS300 & IS300)»(ref-134931-S40604597622002022100000) table. VALVE CLEARANCE SPECIFICATIONS (GS300 & IS300) Application (1) In. (mm) Intake.006-.010 (.15-.25) Exhaust.010-.014 (.25-.35) (1) Adjust valve clearance with engine cold.
- 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.
- Valve Clearance Adjuster (SST 09248-55040) is used for adjusting valve clearance. Press valve lifter downward using SST "A" of valve clearance adjuster. (Scheme 22) Install SST "B" between camshaft and valve lifter with side marked with No. 7 or No. 9 at designated position. (Scheme 22) 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.
- 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 17)and (Scheme 18).
- 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.
- Install No. 2 camshaft bearing cap if removed. Tighten camshaft bearing cap bolts to specification. See «TORQUE SPECIFICATIONS»(ref-134931-S14922654382002022100000).
- 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 23). Tighten bolts/nuts to specification. See «TORQUE SPECIFICATIONS»(ref-134931-S14922654382002022100000). Fill cooling system.
Scheme 24
Scheme 25
Scheme 26
Scheme 27
- Remove intake manifold cover located on top of engine. 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.
- On LX470, 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. Disconnect necessary hoses, hose brackets and engine wiring brackets for access to valve covers. Remove bolts, seal washers, valve covers and gaskets.
- 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 24)- (Scheme 25).
- On GS430, LS430 and SC430, ensure timing marks on back of camshaft sprockets are aligned. (Scheme 26) On LX470, ensure timing marks on camshaft sprockets are aligned with timing marks on timing belt rear plate. (Scheme 27) 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 lower timing belt cover.
- On GS430, LS430 and LX470, use feeler gauge and 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 24) Record valve clearance. 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 24) Record valve clearance.
- On SC430, use feeler gauge and measure valve clearance between valve lifter and camshaft on intake valves on cylinders No. 1, 2, 5 and 7, and exhaust valves on cylinders No. 1, 3, 4 and 8. Perform STEP 1. (Scheme 25) Record valve clearance. 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, 6 and 8, and exhaust valves on cylinders No. 2, 5, 6 and 7. Perform STEP 2. (Scheme 25) Record valve clearance.
- On all models, ensure valve clearance is within specification. See «VALVE CLEARANCE SPECIFICATIONS (GS430, LS430, LX470 & SC430)»(ref-134931-S31154060602002022100000) table. VALVE CLEARANCE SPECIFICATIONS (GS430, LS430, LX470 & SC430) Application (1) In. (mm) Intake.006-.010 (.15-.25) Exhaust.010-.014 (.25-.35) (1) Adjust valve clearance with engine cold.
- 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 CAMSHAFT under REMOVAL & INSTALLATION in appropriate ENGINES article.
- 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 28)- (Scheme 29). Install adjusting shim, valve lifter, camshafts and timing belt. Recheck valve clearance.
- If spark plug tube gasket in valve cover requires replacement, bend gasket retaining tabs upward. Pry spark plug tube gasket from valve cover. Use care not to scratch valve cover sealing surface.
- 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 tabs downward. Coat spark plug tube gasket sealing area with grease.
- Before installing valve covers and gaskets, apply sealant at specified areas on cylinder head. (Scheme 30) 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-134931-S14922654382002022100000).
- To install remaining components, reverse removal procedure. Tighten bolts/nuts to specification. See «TORQUE SPECIFICATIONS»(ref-134931-S14922654382002022100000). Refill cooling system if drained.
Scheme 28
Scheme 29
Scheme 30
IGNITION TIMING
Note. ES300 information is not available. Data link connectors No. 1 or 3 may also be referred to as DLC1 or DLC3.
GS300 & IS300
- Start and warm engine up to normal operating temperature. Shut engine off. Connect scan tool to DLC3. (Scheme 31) Use scan tool to read engine RPM. Using a timing light that can detect primary ignition signal, connect inductive lead to appropriate wire at ignitor. (Scheme 32) Ignitor is located on top of driver's side strut tower.
- 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. On GS300, install Jumper Wire (SST 09843-18020) between terminals TC and E1 on DLC1 located near driver's side strut tower. (Scheme 33) On IS300, install Jumper Wire (SST 09843-18020) between terminals TC and CG on DLC3 located under right side of instrument panel. (Scheme 34)
- 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. Remove jumper wire from DLC1. Ensure ECM controlled timing is 6-16 degrees BTDC. Shut engine off. Remove timing light and scan tool.
Scheme 31
Scheme 32
Scheme 33
Scheme 34
LX470
- Start and warm engine up to normal operating temperature. Shut engine off. Remove intake manifold cover located on top of engine, battery clamp cover and intake air connector. Connect scan tool to DLC3. (Scheme 31) Use scan tool to read engine RPM.
- Connect timing light lead to wire at ignition coil electrical connector on top of driver's side valve cover at cylinder No. 1. (Scheme 35) Cylinder No. 1 is front cylinder on left side of engine when viewed from flywheel end of engine. (Scheme 24)
- 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.
- Install Jumper Wire (SST 09843-18020) between terminals TC and E1 on DLC1 located on passenger's side front fender. (Scheme 36)
- Check timing marks 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, battery clamp cover and intake air connector.
Scheme 35
Scheme 36
RX300
- Remove intake manifold cover. (Scheme 13) Start and warm engine up to normal operating temperature. Shut engine off. Connect scan tool to DLC3. (Scheme 31) Use scan tool to read engine RPM.
- Connect timing light lead to Black/Red wire at ignition coil electrical connector on top of front valve cover at cylinder No. 4. (Scheme 37) Open wiring harness cover to gain access if necessary. Cylinder No. 4 is second cylinder on left side when viewed from flywheel end of engine. (Scheme 14)
- 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.
- Install Jumper Wire (SST 09843-18020) between terminals TE1 and E1 on DLC1. (Scheme 38) DLC1 is located on end of air intake chamber at passenger's side of engine compartment.
- 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.
- Remove jumper wire from DLC1. Ensure ECM controlled timing is 10-25 degrees BTDC. Shut engine off. Remove timing light and scan tool. Reinstall intake manifold cover.
Scheme 37
Scheme 38
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.
Note. Data link connectors No. 1 or 3 may also be referred to as DLC1 or DLC3.
ES300 & SC430
- Start and warm engine up to normal operating temperature. Shut engine off.
- Connect scan tool to DLC3. (Scheme 31) Use scan tool to read engine RPM.
- Apply parking brake. Place transaxle in Neutral. Start engine warm to normal operating temperature, then allow engine to idle. On ES300, ensure idle speed is 550-650 RPM. On SC430, ensure idle speed is 700-800 RPM.
- If idle speed is not within specification, check throttle body assembly. See THROTTLE BODY under THROTTLE CONTROLS in appropriate SYSTEM & COMPONENT TESTING article. Shut engine off. Remove scan tool.
GS300, IS300, GS430, LS430, LX470 & RX300
- Start and warm engine up to normal operating temperature. Shut engine off. Connect scan tool to DLC3. (Scheme 31) Use scan tool to read engine RPM.
- 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-134931-S29243941432002022100000) table. IDLE SPEED SPECIFICATIONS Application Idle RPM GS300, IS300, LX470 & RX300 650-750 GS430 & LS430 700-800
- If idle speed is not within specification on RX300, check IAC valve and air intake system. On all other models, 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.
THROTTLE POSITION (TP) SENSOR
Note. Testing information for SC430 is not available.
Adjusting TP Sensor
Note. Data link connectors No. 1 or 3 may also be referred to as DLC1 or DLC3.
- Loosen 2 sensor mounting screws. Turn TP sensor until it no longer contacts throttle valve shaft. Turn TP sensor back until it just starts to touch throttle valve shaft, then snug mounting screws. On GS300, IS300 and LX470, disconnect accelerator pedal position sensor connector. On all models, connect scan tool to DLC3. (Scheme 31) Go to next step.
- Turn ignition switch on. DO NOT depress accelerator pedal. On scan tool, select CURRENT DATA, then THROTTLE POS. Slowly turn TP sensor until value is as specified. See «TP SENSOR SPECIFICATIONS»(ref-134931-S16861593792002022100000) table. Tighten sensor mounting screws. Go to next step. TP SENSOR SPECIFICATIONS Model Scan Tool Value (Percent) ES300 16.0-17.6 GS300 & IS300 14.0-15.6 GS430, LS430 & LX470 14.4-16.0 SC430 15.6-19.6
- Using screwdriver where necessary, push throttle valve completely closed. Recheck scan tool TP sensor value. Value should be 10-14 percent. If value is not as specified, go back to step 1. If value is as specified, on GS300, IS300 and LX470, reconnect accelerator pedal position sensor connector.
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
| Application | Ft. Lbs. (N.m) |
|---|---|
| Spark Plug | 13 (18) |
| INCH Lbs. (N.m) | |
| Ignition Coil Bolt | 69 (8.0) |
TORQUE SPECIFICATIONS (ES300)
| Application | Ft. Lbs. (N.m) |
|---|---|
| Camshaft Bearing Cap Bolt | 15 (20) |
| Intake Air Connector-To-Air Intake Chamber Bolt/Nut | 21 (28) |
| Spark Plug | 13 (18) |
| Throttle Body Bracket-To-Cylinder Head Nut | 15 (21) |
| Throttle Body Gasket Bolts | 15 (21) |
| INCH Lbs. (N.m) | |
| Ignition Coil Bolt | 71 (8.0) |
| Upper Timing Belt Cover Bolt | 71 (8.0) |
| Valve Cover Bolt/Nut | 75 (8.5) |
TORQUE SPECIFICATIONS (GS300 & IS300)
GS430, LS430, LX470 & SC430
| Application | Ft. Lbs. (N.m) |
|---|---|
| Spark Plug | 13 (18) |
| Throttle Body Bolt/Nut | 13 (18) |
| INCH Lbs. (N.m) | |
| Ignition Coil Bolt | 66 (7.5) |
| Upper Timing Belt Cover Bolt/Nut | 66 (7.5) |
TORQUE SPECIFICATIONS (GS430, LS430, LX470 & SC430)
| Application | Ft. Lbs. (N.m) |
|---|---|
| Air Intake Chamber Bolt/Nut | 32 (43) |
| No.1 Engine Hanger Bolt | 29 (39) |
| Spark Plug | 13 (18) |
| Suspension Upper Brace Bolt | 59 (80) |
| Throttle Body Brace Bolt | 15 (20) |
| Windshield Wiper Arm Nut | 18 (24) |
| INCH Lbs. (N.m) | |
| Ignition Coil Bolt | 69 (8.0) |
| Valve Cover Bolt | 69 (8.0) |
TORQUE SPECIFICATIONS (RX300)