Off Vehicle Inspection
INSPECTION1. Clean throttle body.
- Using a soft brush and carburetor cleaner, clean the cast parts.
- Using compressed air, clean all the passages and apertures.
NOTE: To prevent deterioration, do not clean the Throttle Position Sensor or Dashpot.
2. Inspect throttle valve.
- Apply vacuum to the Throttle Opener.
- Check that there is no clearance between the throttle stop screw and throttle lever when the throttle valve is fully closed.
3. Inspect Throttle Position Sensor.
- Apply vacuum to the Throttle Opener.
- Insert a thickness gauge between the throttle stop screw and stop lever.
- Using an ohmmeter measure the resistance between each terminal.
Clearance between Between Resistance
lever and stop screw terminals
0 mm (0 in) VTA1 - E2 0.34 - 6.3 k ohms
0.40 mm (0.016 in) IDL1 - E2 0.5 k ohms or less
0.60 mm (0.024 in) IDL1 - E2 Infinity
Wide open throttle VTA1 - E2 2.4 - 11.2 k ohms
Always VC - E2 3.1 - 7.2 k ohms
4. If necessary, adjust Throttle Position Sensor.
- Loosen the 2 set screws of the sensor.
- Apply vacuum to the Throttle Opener.
- Insert a 0.50 mm (0.020 in.) thickness gauge. between the throttle stop screw and stop lever.
- Connect the test probe of an ohmmeter to the terminals IDL1 and E2 of the sensor.
- Gradually turn the sensor clockwise until the ohmmeter deflects, and secure the sensor with the 2 set screws.
- Recheck the continuity between terminals IDL1 and E2.
With 0.40 mm (0.016 in) clearance between lever and stop screw you should measure continuity.
With 0.60 mm (0.024 in) clearance between lever and stop screw you should measure NO continuity.
5. Inspect Sub Throttle Position Sensor, Sub Throttle Actuator and Sub Throttle Valve (vehicles with TRAC only).
- Inspect Sub Throttle Actuator. Using an ohmmeter measure the resistance between the terminals ACM and A, ACM and A-, BCM and B, BCM and B-.
Resistance: 0.5 - 1.0 ohms
- If the resistance is not as specified, replace the Actuator.
- Inspect the Sub Throttle Valve. Remove the four screws and remove and Sub Throttle Actuator. Verify that there is no clearance between the throttle stop screw and throttle gear when the Sub Throttle Valve is fully closed.
- Inspect Sub Throttle Position Sensor. Insert a 0.30 mm (.012 in) / 0.50 mm (0.020 in) feeler gauge between the throttle stop screw and Throttle Valve gear. Usng an ohmmeter, measure the resistance between terminals as indicated below.
Clearance between Between Resistance
lever and stop screw terminals
0 mm (0 in) VTA2 - E2 0.34 - 6.3 k ohms
0.30 mm (0.012 in) IDL2 - E2 0.5 k ohms or less
0.50 mm (0.020 in) IDL2 - E2 Infinity
Wide open throttle VTA2 - E2 2.4 - 11.2 k ohms
Always VC - E2 3.1 - 7.2 k ohms
6. If necessary, adjust the Sub Throttle Position Sensor.
- Loosen the 2 set screws of the sensor.
- Apply vacuum to the Throttle Opener.
- Insert a 0.40 mm (0.016 in.) thickness gauge. between the throttle stop screw and Throttle Valve gear.
- Connect the test probe of an ohmmeter to the terminals IDL2 and E2 of the sensor.
- Gradually turn the sensor clockwise until the ohmmeter deflects, and secure the sensor with the 2 set screws.
- Recheck the continuity between terminals IDL2 and E2.
With 0.30 mm (0.0162 in) clearance between lever and stop screw you should measure continuity.
With 0.50 mm (0.020 in) clearance between lever and stop screw you should measure NO continuity.
7. Reinstall the Sub Throttle Actuator with the four screws.