Throttle Opener System Mitsubishi Montero I

DESCRIPTION

The throttle opener system consists of throttle opener assembly, solenoid valve, engine speed sensor and air conditioning switch. Various models also have provisions for heavy electrical and/or power steering load switches in addition to air conditioning. These include power steering, oil pressure, lighting, defogger and blower switches. When the engine speed sensor detects engine speed at or below specified value, air switching system does not operate. When engine speed is above specified value, air switching system works as designed.

HEAVY ENGINE LOAD

When engine speed sensor detects engine speed at or below specified value, solenoid valve is opened which transfers intake manifold vacuum to throttle opener. Throttle valve is slightly opened by throttle opener and opener lever located on throttle valve shaft. Engine will then run at a speed resulting from new throttle valve opening. When a heavy load condition does not exist, throttle opener system stops working and engine runs at normal speed. The engine speed sensor used in the deceleration spark advance system is usually used in the throttle opener system.

LIGHT ENGINE LOAD

When a light engine load condition exists, throttle opener system stops working and engine runs at normal speed.

THROTTLE OPENER OPERATING SPEED

1. Turn lights and accessories off. Place transmission in Neutral. Run engine until it reaches normal operating temperature. If equipped, electric fan should be off. Be sure curb idle is within specifications.
2. On 1.5L engines, remove vacuum hose from throttle opener. System is working properly if there is no vacuum. On all engines, use test light and check solenoid valve wire connections for current. There should be no current. If current is indicated, inspect electric load, power steering and/or air conditioning switches. If continuity is indicated when switches are in "OFF" position, switches must be replaced.
3. On 1.5L engines, use vacuum pump and apply vacuum to throttle opener. If it can not hold vacuum, throttle opener must be replaced. Push electric load (tail light, defogger and blower) or A/C switch. System is functioning properly if there is vacuum at throttle opener vacuum hose. If no vacuum is indicated, remove manifold vacuum hose from solenoid valve and check for vacuum. If there is no vacuum, clean intake manifold vacuum connection and repeat step.
4. On all engines, if necessary to reset idle speed to specifications, switch A/C or other suitable switches to "ON" position. Adjust engine to specified speed with throttle opener screw. Turn A/C or other switch on and off several times to check for throttle lever operation.

THROTTLE OPENER SPECIFICATIONS

THROTTLE OPENER SPECIFICATIONS