my Cadillac Escalade T1XX (2021-Present) doesn't respond when I press the gas

Symptoms

• Check engine light illuminated
• Engine cranks but does not start
• Rough idle or stalling
• Unresponsive throttle during acceleration
• Poor fuel economy
• Unusual engine noises (e.g., sputtering or backfiring)

Diagnostic Steps

1. Scan for error codes using an OBD-II scanner to identify any stored trouble codes.
2. Check fuel pressure using a fuel pressure gauge to ensure the fuel pump is delivering adequate pressure.
3. Inspect the throttle body for carbon buildup or physical obstructions.
4. Verify the operation of the accelerator pedal position sensor by testing its signal with a multimeter.
5. Check the wiring and connectors for the throttle system for signs of damage or corrosion.
6. Inspect the air intake system for any blockages or leaks that could affect airflow.

Solution

1. Preparation

• Gather necessary tools and parts.
• Ensure the vehicle is parked on a level surface and the engine is cool.
• Disconnect the negative battery terminal to prevent electrical shock.

2. Fuel Pressure Check

• Tools Required: Fuel pressure gauge, safety glasses, rags.
• Locate the fuel rail test port and attach the fuel pressure gauge.
• Turn the ignition to the "ON" position (do not start the engine) and observe the pressure reading. It should be within the manufacturer's specified range (typically around 55-62 psi for most GM vehicles).
• If pressure is low, check the fuel pump fuse and relay, then inspect the fuel lines for leaks.

3. Throttle Body Inspection

• Tools Required: Socket set, cleaning solution, throttle body cleaner.
• Remove the air intake duct connecting to the throttle body by loosening the clamps and disconnecting any sensors.
• Inspect the throttle body for carbon buildup. Clean with throttle body cleaner and a soft cloth.
• Ensure the throttle plate moves freely when the accelerator pedal is pressed. If it sticks, replace the throttle body.

4. Accelerator Pedal Position Sensor Testing

• Tools Required: Multimeter.
• Locate the accelerator pedal position sensor connector (usually found near the pedal assembly).
• Disconnect the sensor and test the signal wire for continuity and proper voltage according to the manufacturer's specifications.
• If the readings are outside the specifications, replace the accelerator pedal position sensor.

5. Reassembly and Battery Reconnection

• Reconnect any components and connectors that were removed during inspection.
• Reinstall the air intake duct and ensure all clamps are secure.
• Reconnect the negative battery terminal.