Tune-up and Engine Performance Checks: Testing and Inspection
ENGINE TUNE-UPEngine Tune-up Preparation
1. Warm up the engine to normal operating temperature.
2. Shift transmission into Neutral (MT) or P position (AT).
3. Turn off all electrical loads.
^ Headlight
^ Blower
^ Rear window defroster
4. Verify that the battery is fully charged.
5. Wait until the electrical fan stops.
7. Access RPM PID.
8. If using the SST (System selector) to turn on the test mode, perform as follows:
1) Connect the SST to the DLC.
2) Set switch A to position 1.
3) Set the test switch to SELF TEST.
Caution:
^ Connecting to the wrong DLC terminal may possibly cause a malfunction. Carefully connect to the specified terminal only.
9. If using a jumper wire to turn on the test mode, perform the following:
1) Short the DLC terminal TEN to body GND using a jumper wire.
10. Select "START" to begin.
Ignition Timing Inspection
1. Perform "Engine Tune-up Preparation".
2. Verify that the idle speed is within the specification.
^ If not as specified, adjust the idle speed.
Specification 750 - 850 (800 ± 50) rpm
3. Connect a timing light to the high-tension lead of the No. 1 cylinder.
4. Verify that the timing mark (white) on the crankshaft pulley and the T mark on the timing belt cover are aligned.
Ignition timing BTDC 9° - 11° (10° ± 1°) (TIMING MARK [YELLOW])
5. Disconnect SST (System selector) or a jumper wire.
6. Press "CANCEL".
7. Verify that the timing mark (yellow) is within the specification.
^ If not as specified, inspect the following.
- CMP sensor
- CKP sensor
- TP sensor
- ECT sensor
- Neutral switch (MT)
- Clutch switch (MT)
- TR switch (AT)
^ If the devices are normal, replace the PCM.
Specification BTDC 6° - 18°
Idle Speed Adjustment
1. Perform "Engine Tune-up Preparation".
2. Verify that the idle speed is within the specification.
^ If not within the specification, adjust the idle speed by turning the AAS.
Specification 750 - 850 (800 ± 50) rpm
Caution:
^ The AAS is set at the factory and must not be adjusted. Any adjustment will negatively affect the engine performance.
3. Disconnect SST (System selector) or a jumper wire.
4. Press "CLEAR" to clear previously selected items.
5. Disconnect the scan tool.
Idle-up Speed Inspection
1. Perform "Engine Tune-up Preparation", and "Idle Speed Adjustment".
2. Verify "RPM" PID is selected.
3. Press "START".
4. Verify that the idle speed is normal.
5. Verify that the idle-up speed is within the specification.
^ If not as specified under all load conditions, inspect the IAC valve.
^ If not as specified under some load conditions, inspect related input switches, harnesses and connectors.
*4: Excludes temporary idle speed drop just after the electrical loads (E/L) are turned on.
*2: Headlight is on, fan switch (above 1st), cooling fan are operating, rear window defroster is on.
*3: Steering wheel is fully turned.
*4: A/C switch and fan switch are on.
Idle Mixture Inspection
1. Perform "Engine Tune-up Preparation".
2. Verify that the idle speed and ignition timing are within the specification.
3. Insert an exhaust gas analyzer to the tailpipe.
4. Verify that the CO and HO concentrations are within the regulation.
^ If not, inspect the following.
- OBD system
- H02S
- Intake manifold vacuum
- Fuel line pressure
- Ignition timing control
^ If the systems are normal, replace the TWC.