Ignition Timing
- Engine must be at operating temperature. Connect tachometer and timing light to engine. Connect test probe of tachometer to negative (-) terminal of coil, or to the service connector on distributor (if equipped). Adjust idle speed to specifications.
- On 3A-C and 4A-C engines (Tercel and Corolla), disconnect and plug INBOARD distributor vacuum line only. On all other engines, disconnect and plug both distributor vacuum lines. On all models, adjust timing by turning distributor.
IGNITION TIMING (DEGREES BTDC @ RPM)
| Application | Timing Vac. Plugged | Timing Vac. Connected | |
|---|---|---|---|
| Corolla | 5° @ 950 | N/A | |
| Tercel | |||
| Man. Trans. | 5° @ 950 | 13° @ Idle | |
| Auto. Trans. | 5° @ 950 | 13° @ Idle | |