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2004 CADILLAC STS

4.6L V8RWDAUTOMATICgas
Repairs0Labor503Torque3859Fluid7DTC779Battery0Maintenance0Recalls0
P0316moderate severityPowertrain

Engine Misfire Detected on Startup (First 1000 Revolutions)

on 2004 Cadillac STS 4.6L V8 · RWD

What this code means

Misfire detected during the first 1000 engine revolutions after startup.

Symptoms

  • Check Engine Light after cold start
  • Rough start then smooths out
  • Stumble on startup

Common causes

  • Leaking fuel injector (dripping when off)
  • Loss of fuel pressure after shutdown
  • Spark plug fouled from previous shutdown

Diagnostic steps

  1. Perform fuel pressure leak-down test
  2. Check injectors for leaks
  3. Inspect spark plugs
  4. Monitor misfire counts on cold start

Repair notes

Check for leaking injectors. Replace fouled spark plugs.

Other Powertrain codes on this vehicle

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