P2300high severityPowertrain
Ignition Coil A Secondary Circuit Insufficient Ionization
on 1997 Toyota 4Runner 2.7L I4 · 4WD
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.
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