Install tachometer. Tachometer must be connected to proper terminals. See IDLE SPEED & MIXTURE in ADJUSTMENTS article in the ENGINE PERFORMANCE Section.
CAUTION: Some tachometers may not be compatible with ignition system. Consult tachometer manufacturer before connecting tachometer to system. To avoid possible damage to ignitor and/or coil, DO NOT allow tachometer terminal to become grounded.
Disconnect electrical connector from throttle position sensor. Install jumper wire between IDL and E2 terminals on wiring harness side. See Fig 1.
Start engine and warm to normal operating temperature. Ensure all accessories are off. Gradually increase engine RPM. Note fluctuation in tachometer reading to indicate the fuel cut RPM and fuel return RPM. See Fig 2.
Ensure fuel cut and fuel return RPM are within specification. See FUEL CUT SYSTEM SPECIFICATIONS table under FUEL CUT SYSTEM (ALL OTHERS). Shut engine off and disconnect tachometer. Reinstall electrical connector on throttle position sensor.

Fig 1: Identifying Throttle Position Sensor Connector Terminals

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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.

Safety Warning

Fuel Cut System