1985 Chevrolet Spectrum 2D Hatchback, AutomaticFACTORY OEM SERVICE PROCEDURE

Throttle Position Sensor

The throttle position sensor assembly consists of an idle switch, used to determine idle position, and a throttle position switch used to sense pre-wide open throttle (WOT) and WOT position.

The throttle position sensor assembly (TPS) is connected to throttle shaft of carburetor. The TPS provides a voltage which is a function of throttle angle.

It enables ECM to read throttle position so ECM can sense pre-WOT and WOT position. The purpose of using TPS for a manual transmission is to inform ECM of engine load for gear shift indicator light system.

Factory Service Tools

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When to See a Mechanic

Stop DIY work and contact a certified mechanic immediately if any of the following apply:

  • β€’ You smell fuel, burning insulation, or see smoke.
  • β€’ Brakes feel soft, pull hard to one side, or make grinding noises.
  • β€’ The engine overheats, stalls repeatedly, or misfires under load.
  • β€’ You are missing required tools, torque specs, or safe lifting equipment.
  • β€’ You are not confident in the next step or safety outcome.