Safety Warning
DIY auto repair can cause serious injury, fire, or vehicle damage. These guides are for informational purposes only. Always follow OEM torque specs, wear PPE, and consult a certified mechanic if you are unsure. You are solely responsible for your safety.
Idle Speed Control (ISC) System
The ISC System provides start control, fast idle control, idle control and dashpot control. Start control adjusts throttle valve opening to optimum position according to engine coolant temperature.
Fast idle control is determined by position of idle switch. When idle switch is on, engine speed is controlled according to engine coolant temperature. When idle switch is off, ISC servo is actuated according to engine coolant temperature.
Idle control increases idle speed when A/C switch is turned on or when transmission is shifted from Neutral to Drive (automatic transmission only). Dashpot control delays closing of throttle valve to its normal idling position. This delay absorbs shock at the time of deceleration for better driving comfort.
Use the Manual With the Right Hardware
Pair factory procedures with proven DIY tools so the instructions are easier to execute.
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When to See a Mechanic
Stop DIY work and contact a certified mechanic immediately if any of the following apply:
- • You smell fuel, burning insulation, or see smoke.
- • Brakes feel soft, pull hard to one side, or make grinding noises.
- • The engine overheats, stalls repeatedly, or misfires under load.
- • You are missing required tools, torque specs, or safe lifting equipment.
- • You are not confident in the next step or safety outcome.
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