why is my Cadillac Escalade T1XX (2021-Present) using so much gas lately

Symptoms

• Check engine light illuminated
• Noticeable decrease in miles per gallon (MPG)
• Engine stalling or rough idling
• Strong smell of fuel during operation
• Increased emissions from the exhaust
• Frequent need to refuel

Diagnostic Steps

1. Scan for error codes using an OBD-II scanner to identify any diagnostic trouble codes (DTCs).
2. Check the fuel pressure using a fuel pressure gauge to ensure it is within manufacturer specifications.
3. Inspect the air filter for clogs or restrictions that may affect airflow.
4. Examine the fuel injectors for leaks or blockages.
5. Inspect the exhaust system for any signs of blockage or damage.
6. Monitor the engine's vacuum levels using a vacuum gauge to check for leaks.

Solution

1. Preparation

• Gather tools and parts. Ensure the vehicle is parked on a level surface.
• Disconnect the battery to ensure safety while working on the fuel system.

2. Fuel System Inspection

• Fuel Pressure Check:

  • Connect a fuel pressure gauge to the fuel rail.
  • Turn the ignition to the "ON" position (do not start the engine) and check the pressure reading.
  • Compare the reading to manufacturer specifications (usually around 55-62 psi for most GM vehicles).
  • If pressure is low, proceed to check the fuel pump.

• Inspect Fuel Injectors:

  • Remove the engine cover if necessary.
  • Visually inspect the fuel injectors for signs of leaks or cracks.
  • Use a multimeter to test injector resistance; if out of range, replace the injector.

3. Air Intake and Filter Inspection

• Remove the air intake duct.
• Check the air filter; if dirty or clogged, replace it with a new one.
• Inspect the air intake duct for any leaks or restrictions and clean if necessary.

4. Exhaust System Inspection

• Inspect the exhaust system visually for any leaks, blockages, or damages.
• If a blockage is suspected, perform a backpressure test to determine if the catalytic converter is clogged.

5. Vacuum System Check

• Connect a vacuum gauge to a vacuum source on the intake manifold.
• Start the engine and observe the gauge; normal idle should show between 17-21 inches of mercury.
• If readings are low or fluctuate significantly, check for vacuum leaks in hoses and intake.