P2300high severityPowertrain
Ignition Coil A Secondary Circuit Insufficient Ionization
on 2004 Subaru Legacy 3.0L H6 · AWD
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
- Check spark plug condition
- Measure coil secondary resistance
- Compression test
- Inspect plug wire
Repair notes
Replace spark plug first. Replace coil if fault persists.
Other Powertrain codes on this vehicle
P0001
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P0002
Fuel Volume Regulator Control Circuit Range/Performance
P0003
Fuel Volume Regulator Control Circuit Low
P0004
Fuel Volume Regulator Control Circuit High
P0010
Intake Camshaft Position Actuator Circuit/Open Bank 1
P0011
Intake Camshaft Position Timing Over-Advanced Bank 1
P0012
Intake Camshaft Position Timing Over-Retarded Bank 1
P0013
Exhaust Camshaft Position Actuator Circuit/Open Bank 1
P0014
Exhaust Camshaft Position Timing Over-Advanced Bank 1
P0015
Exhaust Camshaft Position Timing Over-Retarded Bank 1