When testing fuel cut system, engine RPM must be monitored using scan tester. Connect scan tester to data link connector No. 3 for monitoring engine RPM. For connecting of scan tester, see appropriate application under IDLE SPEED & MIXTURE in ADJUSTMENTS article.

Start and warm engine to normal operating temperature. Ensure the A/C and all accessories are off. Gradually increase engine RPM to maintain at least specified engine speed. See FUEL CUT SYSTEM TESTING SPECIFICATIONS table.

FUEL CUT SYSTEM TESTING SPECIFICATIONS

Application	Engine RPM
Tercel	2500

Using stethoscope, check for fuel injector operating sound. Ensure when throttle lever is released, fuel injector stops operating momentarily and then resumes operating (fuel return RPM).
Ensure fuel return RPM is within specification. See FUEL CUT SPECIFICATIONS table. Shut engine off. Remove test equipment.

FUEL CUT SPECIFICATIONS ⁽¹⁾

Application

Fuel Return RPM

Tercel

900

⁽¹⁾	Check with engine at normal operating temperature and with the A/C off.

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

Use the Manual With the Right Hardware

When to See a Mechanic

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