# P0300 — Random/Multiple Cylinder Misfire Detected

> ClearTheCode diagnostic code reference (not OEM service data).

Source: https://clearthecode.com/codes/P0300

**System:** Powertrain · Ignition / Misfire

**Severity:** severe

## Description

The engine is misfiring across multiple cylinders. Most common causes: worn spark plugs, failing ignition coils, vacuum leak, low fuel pressure, bad fuel injectors, low compression. Start by checking plugs and coils.

## Diagnostic snapshot

- **Difficulty:** 6/10 — Intermediate diagnostics
- **Est. repair cost:** $120 – $450
- **Common symptoms:** Misfire or hesitation under load, Rough idle, Check engine light (MIL), Reduced power / limp mode

## Diagnostic workflow

1. Confirm P0300 with a live scan — note pending vs stored and freeze frame data.
2. Verify reported symptoms: Misfire or hesitation under load, Rough idle, Check engine light (MIL).
3. Inspect wiring/connectors and related sensors before replacing modules.
4. Most likely fixes: Spark plug / coil / ignition diagnosis; Cylinder-specific misfire diagnosis (swap / compression / injector); Fuel injector / circuit testing (noid light, resistance, swap).
5. Clear codes and road-test; re-scan after two drive cycles if the monitor must set.

## Likely fixes

1. **Spark plug / coil / ignition diagnosis** (moderate)
2. **Cylinder-specific misfire diagnosis (swap / compression / injector)** (moderate)
3. **Fuel injector / circuit testing (noid light, resistance, swap)** (moderate)

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