1990 Chevrolet Lumina APVFACTORY OEM SERVICE PROCEDURE

Circuit Description

When the fuel pump is running, fuel is delivered to the injector(s) and then to the regulator where the system pressure is controlled to about 9-13 psi. Excess fuel is then returned to the fuel tank.

NOTE: Numbers below refer to circled numbers on diagnostic chart.
Factory Service Tools

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Pair factory procedures with proven DIY tools so the instructions are easier to execute.

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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.