1992 Geo Prizm Base, AutomaticFACTORY OEM SERVICE PROCEDURE

Chart A-9 Cold Start Injector

Cold start injector provides additional fuel during cranking mode to improve engine starting during cold temperatures. Voltage is received from starter solenoid to cold start switch. Cold start switch also may be referred to as cold start injector timer. Cold start test switch provides a ground path for cold start injector during cranking when coolant temperature is less than 95Β°F (35Β°C). Amount of time cold start switch will be on depends on coolant temperature. Cold start test switch is located in coolant passage on front side of engine. Cold start test switch contains a 2-wire connector with Black and Green wires.

NOTE: Test numbers refer to test numbers on diagnostic chart.
  1. Release fuel pressure before installing fuel pressure gauge. See BASIC TESTING article in this section. Disconnecting distributor connectors will disable the other fuel injectors. Amount of decrease in fuel pressure depends on engine temperature.
  2. This checks for power at cold start fuel injector.
  3. This checks for ground source at cold start fuel injector.
  4. This checks for power at cold start fuel injector timer.
Fig 1: Chart A-9 Schematic, Cold Start Injector
G92B25883Courtesy of GENERAL MOTORS CORP.
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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.