my Alfa Romeo Giulia 952 (2016-Present) has an engine warning light, what could it be?

Symptoms

• Check engine light illuminated
• Reduced engine performance
• Rough idle when stationary
• Increased fuel consumption
• Unusual engine noises (such as knocking or pinging)

Diagnostic Steps

1. Scan for error codes using an OBD-II scanner to identify specific diagnostic trouble codes (DTCs).
2. Inspect engine fluid levels (oil, coolant, and transmission fluid) to ensure they are within normal ranges.
3. Check the condition of the air filter for clogs or restrictions.
4. Inspect the spark plugs for wear or fouling.
5. Examine the fuel system for pressure and leaks using a fuel pressure gauge.
6. Verify the function of the throttle body and mass airflow sensor.

Solution

1. Preparation

• Gather necessary tools and safety equipment.
• Ensure the vehicle is parked on a level surface and the engine is cool.
• Disconnect the negative battery terminal to avoid electrical shorts.

2. Addressing Error Codes

• Reconnect the OBD-II scanner to the vehicle and record the specific error codes.
• Research each error code to determine potential issues related to the engine.

3. Fluid Change or Top-Up

• If low fluid levels are detected, top up or change the necessary fluids:
  • Engine oil: Drain and replace with manufacturer-recommended oil.
  • Coolant: Add or replace with the specified coolant type.
• Torque oil drain plug to manufacturer specifications (typically around 25 ft-lbs).

4. Spark Plug Replacement

• Remove the ignition coil packs using a socket set.
• Extract old spark plugs using a spark plug socket.
• Inspect the new spark plugs, ensuring they are gapped correctly and install them.
• Torque the spark plugs to the manufacturer’s specifications (usually around 13 ft-lbs).

5. Throttle Body Cleaning

• Remove the air intake duct to access the throttle body.
• Use throttle body cleaner and a soft brush to clean the throttle plate and inside of the throttle body.
• Reinstall the air intake duct securely.

6. Fuel System Inspection

• Connect a fuel pressure gauge to the fuel rail.
• Turn the ignition to the "ON" position without starting the engine to check fuel pressure.
• If pressure is low, inspect the fuel pump and filter for clogs or failures.