my Alfa Romeo Giulia 952 (2016-Present) loses power when going uphill, what's wrong?

Symptoms

• Check engine light illuminated
• Engine stalling or misfiring
• Decreased acceleration when climbing
• Rough idle during regular operation
• Poor fuel economy noted over time
• Unusual noise from the engine bay

Diagnostic Steps

1. Scan the vehicle's OBD-II system for any error codes related to engine performance.
2. Inspect the air intake system for clogs or leaks that could affect airflow.
3. Check fuel pressure with a gauge to ensure the fuel pump is functioning properly.
4. Examine spark plugs for wear or fouling that could cause misfires.
5. Test the throttle position sensor (TPS) for proper operation using a multimeter.
6. Inspect the exhaust system for blockage or damage that could restrict exhaust flow.

Solution

1. Preparation

• Gather necessary tools and parts.
• Park the vehicle on a level surface and engage the parking brake.
• Disconnect the negative battery terminal to ensure safety.

2. Inspect and Replace Spark Plugs

• Sub-steps:
  1. Remove the engine cover (if applicable) using a socket set.
  2. Disconnect the ignition coil connectors.
  3. Remove ignition coils using a ratchet and appropriate socket.
  4. Extract the spark plugs using a spark plug socket.
  5. Inspect the spark plugs for wear; replace if necessary with OEM parts (NGK or equivalent).
  6. Reinstall spark plugs and ignition coils; reconnect all connectors.

3. Check and Clean Air Intake System

• Sub-steps:
  1. Remove the air intake duct using a flathead screwdriver.
  2. Inspect the air filter; replace if dirty or clogged.
  3. Clean the throttle body using throttle body cleaner and a soft cloth.
  4. Reassemble the air intake system, ensuring all clamps are secure.

4. Fuel System Inspection

• Sub-steps:
  1. Locate the fuel pressure test port on the fuel rail.
  2. Connect the fuel pressure gauge to the test port.
  3. Turn the ignition to the "On" position (do not start) and check the pressure reading against manufacturer specifications.
  4. If pressure is low, check fuel pump operation and replace if necessary.

5. Throttle Position Sensor (TPS) Testing

• Sub-steps:
  1. Locate the TPS on the throttle body.
  2. Disconnect the electrical connector from the TPS.
  3. Use a multimeter to measure the resistance across the sensor terminals while moving the throttle plate.
  4. If readings are inconsistent or out of spec, replace the TPS.