Mazda 323/626/929/GLC/MX-6/RX-7 1978-1989

Throttle Position Sensor



See Figure 1

  1. Unfasten the throttle sensor connector, then connect an ohmmeter across the A and D terminals. The resistance should read 3.5-6.5 ohms.
  3. Connect the ohmmeter across the B and D terminals. Gradually open and close the throttle valve by hand while measuring the resistance. When fully closed, the resistance should be approximately 1k ohms. When fully open the resistance should read 3.5-6.5k ohms.

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Fig. Fig. 1: Throttle position sensor terminal locations-929

  1. If the resistance readings are not as specified, check the throttle sensor idle switch adjustment.

To adjust the throttle sensor idle switch, you will need a set of flat blade feeler gauges.

  1. Connect an ohmmeter across the C and D terminals, then check for continuity across the terminals with a feeler gauge inserted between the throttle stopper screw and throttle valve lever. With a 0.02 in. (0.5mm) feeler gauge inserted, there should be continuity. With a 0.03 in. (0.7mm) feeler gauge, there should be no continuity.
  3. If the switch is not adjusted properly, loosen the throttle sensor retaining screws and move the sensor as required until the continuity readings are as specified. After the adjustment, seal the screws with white paint to retain the setting.