2003 Cadillac CTS StandardFACTORY OEM SERVICE PROCEDURE

Engine Controls - Troubleshooting - No Codes: Introduction

Before diagnosing symptoms or intermittent faults, see DIAGNOSTIC SYSTEM CHECK - ENGINE CONTROLS under SELF-DIAGNOSTIC SYSTEM in SELF-DIAGNOSTICS - 3.2L CTS article. Use this article to diagnose driveability problems when a current DTC is not present.

Symptom checks are intended to direct the technician to malfunctioning component(s) so that further diagnosis may be performed. A symptom should lead to further testing of specific components or systems, or verification of adjustment specifications.

Use intermittent test procedures to locate intermittent driveability problems that do not occur when the vehicle is being tested. These problems may cause a noticeable driveability problem or cause the Malfunction Indicator Light (MIL) to illuminate on some vehicles. See INTERMITTENT CONDITIONSΒ  .

It is also possible that certain driveability concerns have been rectified by the manufacturer through reprogramming the ECM. Check with manufacturer for latest information on updated programs.

NOTE: For specific testing procedures, see SYSTEM & COMPONENT TESTING - 3.2L CTS article. To verify specifications, see appropriate ON-VEHICLE ADJUSTMENTS article, or SERVICE & ADJUSTMENT SPECIFICATIONS article.
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.