Back to 1999 BMW 540iT E39

1999 BMW 540IT E39

4.4L V8RWDAUTOMATICgas
Repairs0Labor595Torque2626Fluid7DTC649Battery0Maintenance0Recalls0
P2300high severityPowertrain

Ignition Coil A Secondary Circuit Insufficient Ionization

on 1999 BMW 540iT E39 4.4L V8 · RWD

What this code means

The ignition system detects insufficient combustion ionization current on cylinder 1 coil.

Symptoms

  • Misfire on cylinder 1
  • Check engine light
  • Rough running

Common causes

  • Worn spark plug
  • Failed ignition coil
  • High resistance plug wire
  • Compression issue

Diagnostic steps

  1. Check spark plug condition
  2. Measure coil secondary resistance
  3. Compression test
  4. Inspect plug wire

Repair notes

Replace spark plug first. Replace coil if fault persists.

Other Powertrain codes on this vehicle

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