Engine Controls - Adjustments - 4-cyl Toyota 4Runner II

ENGINE MECHANICAL

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

CAMRY, CELICA, COROLLA, MR2 & PREVIA

1. Check and adjust valves with engine cold. On Previa, remove 3 screws and right front seat scuff plate. Remove bolt and disconnect right seat belt from floor panel.
2. Remove 4 bolts and right front seat. Remove 2 bolts and right front seat leg. Remove 2 bolts and jack holder. Remove 9 bolts and right engine service hole cover.
3. On all models, remove valve covers. Rotate crankshaft so No. 1 cylinder is at TDC of compression stroke. Ensure timing mark on crankshaft pulley aligns with "0" mark on timing chain cover. Ensure valves on No. 1 cylinder are closed.
4. Measure intake valve clearance on cylinders No. 1 and 2 and exhaust valve clearance on cylinders 1 and 3. (Scheme 1)a feeler gauge, measure and record clearance between valve lifter and camshaft. Ensure clearance is within specification. Refer to the «VALVE CLEARANCE SPECIFICATIONS»(/toyota/4runner/ii-1987-1995/remont/adjustments/#engine-controls-adjustments-4-cyl) table.
5. To check remaining valves, rotate crankshaft 360 degrees (one full turn) until No. 4 piston is at TDC of compression stroke. Measure intake valve clearance on cylinders No. 3 and 4 and exhaust valve clearance on cylinders 2 and 4. (Scheme 1)measurements. nsure clearance is within specifications. Refer to the «VALVE CLEARANCE SPECIFICATIONS»(/toyota/4runner/ii-1987-1995/remont/adjustments/#engine-controls-adjustments-4-cyl) Table.
6. If valves require adjustment, rotate crankshaft so camshaft lobe on valve to be adjusted is facing upward, away from valve lifter.
7. Rotate valve lifter so notch on valve lifter is toward spark plug. Press valve lifter downward using Valve Clearance Adjuster (SST 09248-55010) and SST (A). (Scheme 2)l SST (B) between camshaft and valve lifter. Remove SST (A).
8. Using small screwdriver and magnet, remove adjusting shim. Measure thickness of shim removed. Determine correct thickness of adjusting shim to be used by subtracting appropriate valve clearance specification (See «VALVE CLEARANCE SPECIFICATIONS»(/toyota/4runner/ii-1987-1995/remont/adjustments/#engine-controls-adjustments-4-cyl) table) from measured valve clearance. Add this number to thickness of old shim. Select a new shim with a thickness as close as possible to the calculated value. See appropriate «SHIM THICKNESS SPECIFICATIONS»(/toyota/4runner/ii-1987-1995/remont/adjustments/#engine-controls-adjustments-4-cyl__shim-thickness-specifications) table.
9. Install shim and recheck valve clearance. Install valve cover.

Scheme 1

Scheme 2

VALVE CLEARANCE SPECIFICATIONS

SHIM THICKNESS SPECIFICATIONS

SHIM THICKNESS

SHIM THICKNESS

SHIM THICKNESS

PICKUP & 4RUNNER

1. Check and adjust valve clearance with engine at normal operating temperature. Remove valve cover. Rotate crankshaft pulley and align pulley groove with "0" mark on timing belt cover to set No. 1 cylinder at TDC of compression stroke.
2. Ensure rocker arms on cylinder No. 1 are loose, and rocker arms on cylinder No. 4 are tight. This indicates TDC compression for cylinder No. 1. If rocker arms are not as described, rotate crankshaft 360 degrees and realign timing marks. Check intake valve clearance on cylinders No. 1 and 2, and exhaust valve clearance on cylinders No. 1 and 3; adjust clearance to specification if necessary. Refer to the «VALVE CLEARANCE SPECIFICATIONS»(/toyota/4runner/ii-1987-1995/remont/adjustments/#engine-controls-adjustments-4-cyl) table.
3. Rotate crankshaft 360 degrees and realign timing marks. Adjust intake valve clearance on cylinders No. 3 and 4, and exhaust valve clearance on cylinders No. 2 and 4.

TERCEL

1. Check and adjust valve clearance with engine at normal operating temperature. Remove valve cover. Rotate crankshaft pulley and align pulley groove with "0" mark on timing belt cover to set No. 1 cylinder at TDC of compression stroke.
2. Ensure rocker arms on cylinder No. 1 are loose, and rocker arms on cylinder No. 4 are tight. This indicates TDC compression for No. 1 cylinder. If rocker arms are not as described, rotate crankshaft 360 degrees and realign timing marks.
3. With cylinder No. 1 at TDC compression, measure valve clearance between camshaft lobe and rocker arm using proper thickness feeler gauge. (Scheme 3)«LVE CLEARANCE SPECIFICATIONS»(/toyota/4runner/ii-1987-1995/remont/adjustments/#engine-controls-adjustments-4-cyl) table.
4. Rotate crankshaft 360 degrees and check clearance on remaining camshaft lobes. (Scheme 3)ust valve clearance, loosen lock nut and turn adjusting screw. After proper clearance has been obtained, hold adjusting screw stationary and tighten lock nut. Recheck valve clearance. Install valve cover.

Scheme 3

IGNITION TIMING

1. Ensure engine is at normal operating temperature. Connect timing light to engine. Connect tachometer to proper location. (Scheme 4)
2. Install jumper wire between proper terminals of engine check connector. (Scheme 12) Ensure idle speed is within specification. See appropriate IDLE SPEED SPECIFICATIONS table under IDLE SPEED & MIXTURE. Ensure base timing is within specification. See «IGNITION TIMING»(/toyota/4runner/ii-1987-1995/remont/adjustments/#engine-controls-adjustments-4-cyl) table.
3. Adjust timing by turning distributor.
4. Remove jumper wire from engine check connector and ensure advance timing is within specification. See «IGNITION TIMING»(/toyota/4runner/ii-1987-1995/remont/adjustments/#engine-controls-adjustments-4-cyl) table. Tighten distributor hold-down bolt or cam position sensor bolt. See «TORQUE SPECIFICATIONS»(/toyota/4runner/ii-1987-1995/remont/adjustments/#engine-controls-adjustments-4-cyl) table.

IGNITION TIMING

Scheme 4

Scheme 5

Scheme 6

Scheme 7

Scheme 8

Scheme 9

Scheme 10

Scheme 11

Scheme 12

Scheme 13

Scheme 14

Scheme 15

Scheme 16

Scheme 17

Scheme 18

IDLE MIXTURE

Note. Idle mixture adjustment is not possible on any model. See the G - TESTS W/ CODES article in this section for diagnosis of incorrect idle mixture.

IDLE SPEED

Note. Adjust idle speed with air cleaner installed, all air intake system hoses and vacuum lines connected, electronic fuel injection system wiring connectors tight, transmission/transaxle in Neutral, all accessories and cooling fan off (if equipped) and engine at normal operating temperature.

CAMRY 2.0L

1. Install tachometer to proper terminals. (Scheme 4)l jumper wire between proper terminals of engine check connector. (Scheme 12)e engine at 1000-1300 RPM for 5 seconds then return to idle. Ensure idle speed is within specification. See «IDLE SPEED SPECIFICATIONS»(/toyota/4runner/ii-1987-1995/remont/adjustments/#engine-controls-adjustments-4-cyl) table.
2. If idle speed requires adjustment, remove rubber boot from top of throttle body. (Scheme 19)idle speed adjusting screw to obtain correct idle speed.
3. Remove jumper wire from check connector and ensure idle speed is within specification. See «IDLE SPEED SPECIFICATIONS»(/toyota/4runner/ii-1987-1995/remont/adjustments/#engine-controls-adjustments-4-cyl) table. If idle speed is not within specification, start engine and allow to idle for 30 seconds then shut off.
4. Repeat procedure, if necessary, until idle speed data is stored in control unit and correct idle speed is maintained. Remove tachometer.

Scheme 19

CELICA 1.6L & COROLLA (4A-FE)

1. Install tachometer to proper terminals. (Scheme 5)tart engine and operate at 2500 RPM for about 2 minutes. Allow engine to idle. Install jumper wire between proper terminals of engine check connector. (Scheme 13)Ensure idle speed is within specification. See «IDLE SPEED SPECIFICATIONS»(/toyota/4runner/ii-1987-1995/remont/adjustments/#engine-controls-adjustments-4-cyl) table.
2. If idle speed requires adjustment, remove rubber boot from top of throttle body. (Scheme 19)idle speed adjusting screw to obtain correct idle speed. Remove tachometer.

CELICA 2.0L, MR2 2.0L & PREVIA

1. Install tachometer to proper terminals. (Scheme 6)0. Start engine and check if idle speed is within specification. See «IDLE SPEED SPECIFICATIONS»(/toyota/4runner/ii-1987-1995/remont/adjustments/#engine-controls-adjustments-4-cyl) table.
2. If idle speed is not within specification, check Idle Speed Control (ISC) valve, wiring and ECU. See IDLE CONTROL SYSTEMS in I - SYS/COMP TESTS article in the ENGINE PERFORMANCE Section.

CELICA 2.2L & MR2 2.2L

1. Install tachometer to proper terminals. (Scheme 6)tart engine and operate at 1000-3000 RPM for about 5 seconds. Allow engine to idle. Install check connector jumper wire between proper terminals of engine check connector. (Scheme 13)Ensure idle speed is within specification. See «IDLE SPEED SPECIFICATIONS»(/toyota/4runner/ii-1987-1995/remont/adjustments/#engine-controls-adjustments-4-cyl) table.
2. If idle speed requires adjustment, remove rubber boot from top of throttle body. (Scheme 19)idle speed adjusting screw to obtain correct idle speed. Remove check connector jumper wire and ensure idle speed is within specification. Refer to the «IDLE SPEED SPECIFICATIONS»(/toyota/4runner/ii-1987-1995/remont/adjustments/#engine-controls-adjustments-4-cyl) table. If idle speed is not within specification, start engine and allow to idle for 30 seconds then shut off.
3. Repeat procedure, if necessary, until idle speed data is stored in control unit and correct idle speed is maintained. Remove tachometer.

COROLLA (4A-GE), PICKUP 2.4L, TERCEL & 4RUNNER 2.4L

1. Install tachometer to proper terminals. (Scheme 5)r 11. On Tercel, disconnect idle-up vacuum switching valve connector. On all models, start engine and operate at 2500 RPM for about 2 minutes. Ensure idle speed is within specification. Refer to the «IDLE SPEED SPECIFICATIONS»(/toyota/4runner/ii-1987-1995/remont/adjustments/#engine-controls-adjustments-4-cyl) table.
2. If idle speed requires adjustment, adjust idle speed adjusting screw to obtain correct idle speed. (Scheme 19)tachometer.

IDLE SPEED SPECIFICATIONS

THROTTLE POSITION SENSOR (TPS)

Note. Vehicles with Electronically Controlled Transaxle (ECT) use signals sent from TPS to Electronic Control Unit (ECU) to calculate gear shift and lock-up timing.

1. Loosen mounting screws. Unplug TPS connector. Connect ohmmeter between terminals IDL and E2 (terminals IDL and E1 on Camry 2.0L without ECT). (Scheme 20)
2. To set initial clearance, insert proper thickness feeler gauge between throttle stop screw and throttle lever. See appropriate «THROTTLE POSITION SENSOR ADJUSTMENT»(/toyota/4runner/ii-1987-1995/remont/adjustments/#engine-controls-adjustments-4-cyl) table.
3. With ohmmeter showing infinity, rotate TPS clockwise until continuity exists. Tighten mounting screws. Using specified feeler gauge, recheck adjusted clearance. Disconnect ohmmeter and reconnect TPS after adjustment.

THROTTLE POSITION SENSOR ADJUSTMENT

Scheme 20

Scheme 21

Scheme 22

Scheme 23

DASHPOT CONTROL SYSTEM

For testing and adjustment procedures, see THROTTLE CONTROLS under EMISSION SYSTEMS & SUB-SYSTEMS in I - SYS/COMP TESTS article in this section.

TORQUE SPECIFICATIONS

TORQUE SPECIFICATIONS

See also:
• VALVE CLEARANCE SPECIFICATIONS
• SHIM THICKNESS SPECIFICATIONS