how to fix P0303 code in Ram 1500 DT (2019-Present)

Learn how to diagnose and fix P0303 cylinder 3 misfire in Ram 1500 DT. Step-by-step guide with diagnostic procedures and repair instructions.

Solution

1. Preparation

• Gather necessary tools and parts.
• Disconnect the battery to prevent electrical shorts.
• Allow the engine to cool before beginning work.

2. Replace Spark Plug

• Tools Required: Socket set, torque wrench.
• Remove the engine cover if necessary to access the spark plug.
• Disconnect the ignition coil connector and remove the ignition coil.
• Use a spark plug socket to remove the spark plug from cylinder 3.
• Inspect the old spark plug for wear and gap; install a new spark plug with the correct gap.
• Torque the new spark plug to the manufacturer’s specifications (typically around 13-15 ft-lbs).
• Reinstall the ignition coil and connect the electrical connector.

3. Test and Replace Ignition Coil (if necessary)

• Tools Required: Multimeter.
• Check the resistance of the ignition coil using the multimeter. Refer to the service manual for specific resistance values.
• If the coil is out of spec, remove the faulty ignition coil and replace it with a new one.
• Reconnect the electrical connector to the new ignition coil.

4. Inspect and Replace Fuel Injector (if necessary)

• Tools Required: Fuel injector puller, O-ring lubricant.
• Disconnect the fuel line and electrical connector from the injector.
• Remove the fuel injector using the fuel injector puller.
• Inspect the injector for clogs; clean or replace if necessary.
• Apply O-ring lubricant to the new injector O-rings and install it.
• Reconnect the fuel line and electrical connector.

5. Final Checks

• Reconnect the battery.
• Clear the P0303 code using the OBD-II scanner.
• Start the engine and check for smooth operation.