1988 Cadillac Seville BaseFACTORY OEM SERVICE PROCEDURE

Electronic Control Module (ECM)

The ECM monitors information from various sensors, and controls the systems affecting vehicle performance. Sensor inputs are supplied to the ECM and processed to maintain proper pulse width, correct idle speed and proper spark advance. The ECM also performs a system diagnostic function.

Factory Service Tools

Use the Manual With the Right Hardware

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.