Inspection Of Isc (Idle Speed Control); Inspection Of Idle Speed - TOHATSU MFS 25D Service Manual

Fuel System (Fuel Injection)

10) Inspection of ISC (Idle Speed Control)

1. Use the diagnosis system to check operation of the ISC
(Idle Speed Control) valve. The value may be significantly
higher than the reference value when there is abnormality
in the engine.
ISC Duty Ratio:
10-30% (after warming-up, idle speed 850 min
2. Disconnect hose at intake silencer side of ISC valve, close
the hole from which the hose was disconnected with a
finger to check if engine speed is reduced. Replace the
ISC valve if not.

11) Inspection of Idle Speed

1. Start the engine and run for 5 minutes to warm up.
2. Check the idle speed.
Tachometer:
P/N. 3AC-99010-0
Idle Revolution Speed:
850 min
RPM
4-38
-1 (rpm)
(rpm))
-1
4st 25/30 2022