Ignition Timing: Adjustments

Idle Speed/Ignition Timing/Idle Mixture Ratio Adjustment (A/T MODELS ULEV AND M/T MODELS)

PREPARATION
1. Make sure that the following parts are in good order.
- Battery
- Ignition system
- Engine oil and coolant levels
- Fuses
- ECM harness connector
- Vacuum hoses
- Air intake system
(Oil filler cap, oil level gauge, etc.)
- Fuel pressure
- Engine compression
- Throttle valve
- Evaporative emission system

2. On air conditioner equipped models, checks should be carried out while the air conditioner is OFF.
3. On automatic transmission equipped models, when checking idle rpm, ignition timing and mixture ratio, checks should be carried out while shift lever is in N position.
4. When measuring CO percentage, insert probe more than 40 cm (15.7 in) into tail pipe.
5. Turn off headlamps, heater blower, rear window defogger.
6. Keep front wheels pointed straight ahead.

Overall Inspection Sequence:

OVERALL INSPECTION SEQUENCE

Inspection Procedure (Steps 1 - 2):

Inspection Procedure (Steps 3 - 5):

Inspection Procedure (Steps 6 - 9):

Inspection Procedure (Steps 10 - 14):

Inspection Procedure (Steps 15 - 18):

Inspection Procedure (Steps 19 - 22):

Inspection Procedure (Steps 23 - 26):

Inspection Procedure (Steps 27 - 31):

Inspection Procedure (Steps 32 - 33):

INSPECTION PROCEDURE

Idle Speed/Ignition Timing/Idle Mixture Ratio Adjustment (A/T MODELS EXCEPT ULEV)

PREPARATION
1. Make sure that the following parts are in good order.
- Battery
- Ignition system
- Engine oil and coolant levels
- Fuses
- ECM harness connector
- Vacuum hoses
- Air intake system
(Oil filler cap, oil level gauge, etc.)
- Fuel pressure
- Engine compression
- Throttle valve
- Evaporative emission system

2. On air conditioner equipped models, checks should be carried out while the air conditioner is OFF.
3. On automatic transmission equipped models, when checking idle rpm, ignition timing and mixture ratio, checks should be carried out while shift lever is in N position.
4. When measuring CO percentage, insert probe more than 40 cm (15.7 in) into tail pipe.
5. Turn off headlamp, heater blower, rear window defogger.
6. Keep front wheels pointed straight ahead.
7. Perform inspection after the cooling fans have completely stopped.