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Throttle Position Sensor: Testing and Inspection

Fig. 35 TPS test. 1987-89:






1. Disconnect electrical connector from TPS with ignition off.
2. Measure resistance between terminals 1 and 3, Fig. 35. Ohmmeter should indicate 3.5-6.5k ohms.
3. Connect a suitable ohmmeter between terminals 1 and 2, then slowly operate throttle valve between idle and wide open throttle. Check that resistance values change in proportion to throttle valve operation. The resistance range should vary between resistance value indicated in step 2 and .5k ohms.
4. If resistance values are not as specified, replace TPS.