why does my Ram 1500 DT (2019-Present) have a check engine light with a misfire?

Solution

1. Preparation

• Gather tools: OBD-II scanner, multimeter, socket set, torque wrench, fuel injector cleaning kit, and engine compression tester.
• Ensure the vehicle is parked on a flat surface and the engine is cool.

2. Inspect and Replace Spark Plugs

• Sub-steps:
  1. Remove the engine cover if necessary.
  2. Disconnect the negative battery terminal.
  3. Remove the spark plug wires or ignition coil connectors.
  4. Use a socket set to remove the spark plugs.
  5. Inspect each spark plug for wear; replace with new plugs if they are damaged or worn beyond specification.
  6. Gap the new spark plugs according to manufacturer specifications (usually around 0.040 inches).
  7. Install new spark plugs and reconnect ignition coils/wires.

3. Test and Replace Ignition Coils

• Sub-steps:
  1. Use a multimeter to test each ignition coil for resistance values according to the manufacturer’s specifications.
  2. Replace any faulty ignition coils with OEM or equivalent parts.
  3. Reconnect the ignition coils and battery terminal.

4. Inspect and Clean Fuel Injectors

• Sub-steps:
  1. If injectors are clogged, use a fuel injector cleaning kit to clean them according to the kit instructions.
  2. Alternatively, replace any faulty injectors with new ones.
  3. Reconnect fuel injector connectors after servicing.

5. Verify Air Intake and Vacuum Lines

• Sub-steps:
  1. Inspect all air intake ducts and vacuum lines for cracks or disconnections.
  2. Replace any damaged hoses immediately.
  3. Ensure the air filter is clean and properly seated.

6. Check Engine Compression

• Sub-steps:
  1. Remove the spark plugs to access the cylinders.
  2. Use an engine compression tester to check compression in each cylinder.
  3. If compression is below specifications, further diagnosis of the engine internals may be necessary (e.g., valve issues, head gasket failure).