why does my Cadillac Escalade T1XX (2021-Present) have a rough idle

Symptoms

• Check engine light illuminated
• Engine vibrates noticeably at idle
• Fluctuating RPM at a standstill
• Poor fuel economy
• Engine stalling when coming to a stop
• Increased emissions evident during inspection

Diagnostic Steps

1. Scan for error codes using an OBD-II scanner to identify any stored trouble codes.
2. Inspect engine vacuum lines for leaks or disconnections that could affect air intake.
3. Check the condition of the spark plugs and ignition coils for wear or damage.
4. Test fuel pressure to ensure the fuel system is delivering adequate pressure.
5. Inspect the throttle body for carbon buildup or other obstructions.
6. Monitor the mass airflow (MAF) sensor readings for irregularities.

Solution

1. Preparation

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

2. Inspect and Replace Spark Plugs

• Remove the engine cover (if applicable) using a socket set.
• Locate the ignition coils and disconnect the electrical connectors.
• Remove the ignition coils using a ratchet and socket.
• Use a spark plug socket to carefully remove the spark plugs.
• Inspect the spark plugs for wear; replace them if damaged or fouled.
• Install new spark plugs to the specified torque (typically 13-15 lb-ft).
• Reattach the ignition coils and their connectors.

3. Clean Throttle Body

• Remove the throttle body from the intake manifold by disconnecting the electrical connector and unbolting it.
• Use throttle body cleaner and a soft brush to clean the throttle plate and interior surfaces.
• Ensure no cleaner residue is left behind, then reattach the throttle body.

4. Inspect and Replace MAF Sensor

• Locate the MAF sensor in the air intake duct.
• Disconnect the electrical connector and remove the sensor using a screwdriver.
• Inspect the sensor for dirt or damage; clean with MAF sensor cleaner if dirty.
• Replace if necessary and reattach the sensor.

5. Check Fuel System

• Connect a fuel pressure gauge to the fuel rail test port.
• Turn the ignition key to the "ON" position without starting the engine and check the fuel pressure.
• Compare the pressure reading to the manufacturer specifications (typically 55-62 psi for most models).
• If pressure is low, consider replacing the fuel filter or fuel pump.