Deceleration Fuel-Cut System

Connect a tachometer to engine (to monitor needle fluctuations). See ADJUSTMENTS article in the ENGINE PERFORMANCE Section for tachometer attaching points. Start engine and warm to operating temperature. Ensure A/C and other accessories are off.
Unplug throttle position sensor connector from throttle position sensor. Short terminals IDL and E2 on wire side of connector. See Fig 1.
Gradually raise engine RPM. Fuel-cut operation can be checked by noting the fluctuation of tachometer needle. Fluctuation indicates fuel-cut system is being turned on and off. See Fig 2. Check that fuel-cut points and fuel return points are within specifications. See DECELERATION FUEL-CUT & FUEL RETURN RPM table.

DECELERATION FUEL-CUT & FUEL RETURN RPM

Application

Fuel-Cut RPM

Fuel Return RPM

Pickup

2.4L

2WD ⁽¹⁾ With A/T

1300

1000

All Others

1900

1600

3.0L

1300

1000

4Runner

2.4L

1900

1600

3.0L

1300

1000

⁽¹⁾	Apply service brakes when testing 4-cylinder 2WD automatic transmission.

Fig 1: TPS Sensor Connector Terminal ID

Fig 2: Identifying Needle Fluctuations For Fuel-Cut RPM Test