why does my Acura MDX YF3 (2022-Present) get poor gas mileage all of a sudden

Symptoms

• Check Engine Light (CEL) may illuminate on the dashboard.
• Poor fuel economy, noticeable decrease in miles per gallon (MPG).
• Rough idle or engine stalling during operation.
• Loss of power during acceleration.
• Unusual engine noises or vibrations.
• Increased exhaust emissions or noticeable smell of fuel.

Diagnostic Steps

1. Scan for Error Codes:

   • Use an OBD-II scanner to check for any stored diagnostic trouble codes (DTCs).
   • Look for codes related to fuel system, oxygen sensors, or air-fuel mixture.

2. Check Fluid Levels:

   • Inspect engine oil, transmission fluid, and coolant levels to ensure they are within the proper range.

3. Inspect Air Filter:

   • Check the air filter for dirt and clogging, which can restrict airflow to the engine.

4. Examine Tire Pressure:

   • Ensure tires are inflated to the manufacturer's recommended pressure. Under-inflated tires can negatively affect fuel economy.

5. Inspect Fuel System:

   • Check the fuel filter for blockages and ensure the fuel pump is functioning correctly.
   • Look for leaks in the fuel lines or around the fuel injectors.

6. Test with Multimeter:

   • Test the fuel injectors' resistance with a multimeter to ensure they are functioning correctly.

7. Inspect Exhaust System:

   • Check for blockages or leaks in the exhaust system, particularly in the catalytic converter.

Repair Instructions

If Diagnostic Codes Indicate a Problem:

1. Replace Clogged Air Filter:

   • Remove the air filter housing cover.
   • Replace the old air filter with a new OEM or high-quality aftermarket filter.
   • Reassemble the housing cover.

2. Replace Fuel Filter:

   • Relieve the fuel system pressure by removing the fuel pump fuse and running the engine until it stalls.
   • Disconnect the fuel lines and replace the fuel filter according to the manufacturer's specifications.
   • Reconnect the fuel lines and restore the fuse.

3. Replace Malfunctioning Fuel Injectors:

   • Remove the intake manifold if necessary to access the fuel rail.
   • Disconnect the fuel injector connectors and unscrew the fuel rail.
   • Replace faulty injectors with new ones, ensuring proper seating and sealing.

4. Check Tire Pressure:

   • Inflate tires to the recommended PSI level as indicated on the driver’s door jamb.

5. Repair or Replace Exhaust Components:

   • Inspect the catalytic converter for blockages and replace it if necessary.
   • Repair any leaks in the exhaust system.

Estimated Time for Repair

• Air/Fuel Filter Replacement: 30 minutes
• Fuel Filter Replacement: 1-2 hours
• Fuel Injector Replacement: 2-3 hours
• Exhaust System Inspection/Repair: 1-3 hours depending on the complexity.

Safety Warnings

• Always wear safety gloves and goggles when working on the vehicle.
• Ensure the vehicle is on a flat surface and securely supported when working underneath.
• Relieve fuel system pressure before working on the fuel system to prevent accidents.