Operation CHARM: Car repair manuals for everyone.

Tune-up and Engine Performance Checks: Testing and Inspection




ENGINE TUNE-UP [LF, L3]

Engine Tune-up Preparation

1. Turn off all electrical loads.

2. Warm up the engine as follows.
a. Start the engine.

b. Maintain the engine speed 2,500-3,000 rpm until the cooling fans start to operate.

c. Release the accelerator pedal.

d. Wait until the cooling fans stop.

3. Connect the SST (M-MDS) to the DLC-2.






Ignition Timing Inspection

NOTE:
- Ignition timing is not adjustable.
- Ignition timing verification requires M-MDS.

1. Verify that the ignition timing (M-MDS: SPARKADV PID) is within the specification using M-MDS.

Ignition timing
- Approx. BTDC 8°

2. Verify that ignition timing advances when the engine speed increases gradually.

- If there malfunction, refer to "ENGINE SYMPTOM TROUBLESHOOTING". Symptom Diagnostic Index

Idle Speed Inspection

NOTE:
- Idle speed is not adjustable.
- Idle speed verification requires M-MDS.

1. Verify that the idle speed (M-MDS: RPM PID) is within the specification using M-MDS.

Idle speed [MTX (Neutral position)]
- No load: 600-700 rpm
- Electrical loads*2 ON (38-48 A): 650-750 rpm
- Electrical loads*2 ON (more than 48 A): 700-800 rpm
- A/C ON and refrigerant pressure switch (middle) OFF: 700-800 rpm
- A/C ON and refrigerant pressure switch (middle) ON: 700-800 rpm

Idle speed [ATX (P or N position)]
- No load: 650-750 rpm
- Electrical loads*2 ON (38-48 A): 650-750 rpm
- Electrical loads*2 ON (more than 48 A): 700-800 rpm
- A/C ON and refrigerant pressure switch (middle) OFF: 650-750 rpm
- A/C ON and refrigerant pressure switch (middle) ON: 670-770 rpm

*1
Excludes temporary idle speed drop just after the electrical loads are turned on.
*2
generator generating current value.

- If there malfunction, refer to "ENGINE SYMPTOM TROUBLESHOOTING". Symptom Diagnostic Index

Idle Mixture Inspection

1. Verify that the idle speed and ignition timing are within the specification.

2. Insert an exhaust gas analyzer to the tailpipe.

3. Verify that the CO and HC concentrations are within the regulation.

- If there malfunction, refer to "ENGINE SYMPTOM TROUBLESHOOTING". Symptom Diagnostic Index