P0300 on Dodge: Random or Multiple Cylinder Misfire Detected
Severity: 3 of 4
Park it if the check engine light is flashing or the engine is shaking. A flashing light means misfires severe enough to damage the catalytic converter and in extreme cases cause an exhaust fire. If the light is steady and the misfire is mild, drive only as far as needed to get it diagnosed, gently and without heavy loads.
Estimate range covers the repairs listed below; see the cost breakdown. A flashing check engine light, a hot temperature gauge, or brakes that feel different mean stop driving and get help.
What P0300 usually means on a Dodge
5.7 Hemi engines are frequently reported by owners and repair shops to suffer lifter roller and camshaft wear. We have not found a manufacturer bulletin confirming a defect, so treat it as a reported pattern. A ticking noise and misfire are key signs.
Most likely causes on Dodge vehicles
- Spark plugs (Hemi uses two per cylinder)
- Coils
- Lifter and camshaft wear
- Vacuum leak
Order reflects cost and likelihood in general; your vehicle may differ. Confirm with testing before buying parts.
Dodge specific tips
- Hemis use 16 plugs in a V8, so replacement costs more than you might expect.
- Persistent ticking with misfires needs professional diagnosis.
Estimated repair cost
This is an estimate, built from typical parts price ranges plus labor hours times an assumed shop rate of $110 to $190 per hour. Actual prices vary by vehicle, region, and shop. Diagnosis fees are often extra.
| Repair | Parts | Labor | Estimate (low / high) |
|---|---|---|---|
| Spark plugs, full set | $20 to $120 | 0.5 to 2.5 h | $20 + 0.5 × $110 = $75 $120 + 2.5 × $190 = $595 |
| Vacuum hose or intake gasket | $10 to $120 | 0.5 to 2.5 h | $10 + 0.5 × $110 = $65 $120 + 2.5 × $190 = $595 |
| Ignition coil, one | $30 to $150 | 0.2 to 1.0 h | $30 + 0.2 × $110 = $52 $150 + 1.0 × $190 = $340 |
| Fuel pump | $120 to $600 | 1.5 to 3.5 h | $120 + 1.5 × $110 = $285 $600 + 3.5 × $190 = $1,265 |
Costs are generic for this code; parts and labor on some Dodge models may run higher.
Watch a repair video
How to Fix a Random Engine Misfire in Your Car (Code P0300) (Scotty Kilmer). Third-party video, loads from YouTube (privacy-enhanced mode) only when you press play. Procedures vary by vehicle. Search YouTube for “P0300 Dodge fix” videos.
Repair manuals
Step-by-step service manuals for Dodge with torque specs and wiring diagrams:
Haynes manuals for Dodge Chilton manuals
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Check Dodge recalls
Enter your VIN at the NHTSA recall lookup before paying for repairs.
FAQ
Why does my Hemi tick and misfire?
A worn lifter or camshaft lobe is a common cause; have it inspected.
Read the full P0300 guide or more Dodge check engine notes.