Ignition Timing

Engine must be at operating temperature. Connect timing light to engine. Connect tachometer to negative terminal of coil, engine check connector, or remove rubber cap and connect probe to service connector on distributor (if equipped). See Fig 3 and Fig 4 .
CAUTION: Some tachometers may not be compatible with ignition system. Consult tachometer manufacturer before connecting tach to system. Do not allow tachometer terminal to become grounded. This can damage igniter and/or coil.
Adjust idle speed to specifications. Install jumper wire across terminals of engine check connector (if equipped). See Fig 1 and Fig 2 .
On Tercel and RWD Corolla, disconnect and plug inboard distributor vacuum hose only. On all other models, disconnect and plug both distributor vacuum hoses. Adjust timing by turning distributor.

Fig 1: FWD Corolla EFI (FX16) Ignition Timing Adjustment