Idle Advance System - Toyota 4-Runner 1985 Repair Manual

EC-66
EMISSION CONTROL SYSTEMS (CARB.) - Auxiliary Systems
7. Idle Advance System
With HAC system: Refer to page EC-48 of HAC syste-
A03084
Distributor
EC0407
Fuel Cut Port
Carburetor
Distributor
Throttle Valve
Main Diaphragm
Sub-diaphragm
EC0408
To improve fuel economy at idle, this system advances the ignition timing only while the engine is idling.
Condition Distributor Sub-diaphragm Sub-vacuum Advance
Idling Pulled by fuel cut port vacuum ADVANCED
(+
12°)
Cruising Not pulled NOT ADVANCED