P0300 Ford Bronco
Random/Multiple Cylinder Misfire Detected · Powertrain Code · High · Repair: Moderate
What is P0300?
The ECM has detected misfires occurring in multiple or random cylinders. Common causes include worn spark plugs, faulty ignition coils, vacuum leaks, low fuel pressure, or a failing catalytic converter.
When the Ford Bronco triggers code P0300 (random/multiple cylinder misfire detected), it typically points to an issue in the powertrain system. This is a high severity code, so address it promptly to avoid further damage or safety concerns. Below you'll find the most common causes, symptoms, and repair options specific to the Ford Bronco.
This repair is rated moderate, meaning some experience and specialty tools required.
Diagnostic data on this page is compiled from publicly available repair resources and technical service bulletins. Always have a qualified mechanic confirm the diagnosis before authorizing repairs on your Ford Bronco.
Common Causes on Ford Bronco
- Ignition coil failure on 2.3L EcoBoost four-cylinder under off-road conditions
- Spark plug fouling from extended idle during off-road crawling on 2.7L EcoBoost V6
- Water intrusion into ignition coil connectors from deep water fording
- Carbon buildup on intake valves from GDI system on both 2.3L and 2.7L EcoBoost
- Vacuum leak from intake system damage during off-road use
Symptoms
- Rough idle with noticeable engine vibration
- Engine shaking or stumbling under load
- Loss of power during acceleration
- Check engine light flashing intermittently
- Poor fuel economy
- Hesitation or stumble on acceleration
Notes for Ford Bronco
Off-road use exposes ignition components to water and debris; apply dielectric grease to all electrical connectors.