1991 Geo Tracker LSi, AutomaticFACTORY OEM SERVICE PROCEDURE

Throttle Position Sensor (TPS)

NOTE: To identify throttle position sensor terminals, see Fig 1 .
THROTTLE POSITION SENSOR (TPS) RESISTANCE

Condition Resistance (Ohms)
Between Terminals C & D (1) 0-500
Between Terminals C & D (2) No Continuity
Between Terminals A & D 3500-6500
Between Terminals B & D
At Idle (3) 300-2000
At Wide Open Throttle 2000-6500
(1) With .012" (.30 mm) feeler gauge installed between stop screw and lever.
(2) With .022" (.56 mm) feeler gauge installed between stop screw and lever.
(3) To position throttle valve at idle, apply approximately 18 in. Hg vacuum to throttle opener valve.
Fig 1: Throttle Position Sensor Terminal ID
G121570Courtesy of GENERAL MOTORS CORP.
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