what causes my GMC Sierra T1XX (2019-Present) to stall while driving

Discover the causes and solutions for stalling issues in GMC Sierra T1XX (2019-Present). Step-by-step diagnostic and repair instructions included.

Solution

1. Preparation

• Gather tools and parts needed for repair.
• Ensure the vehicle is parked on a level surface and the engine is cool.
• Disconnect the battery negative terminal for safety.

2. Fuel System Inspection

• Sub-steps:
  1. Connect the fuel pressure gauge to the fuel rail test port.
  2. Turn the ignition key to the "ON" position without starting the engine to check fuel pressure.
  3. If pressure is below specifications (typically around 55-62 psi), inspect the fuel pump and filter for issues.
• Tools Required: Fuel pressure gauge
• Safety Warnings: Fuel can be hazardous; have a fire extinguisher nearby.

3. Ignition System Repair

• Sub-steps:
  1. Remove the engine cover (if applicable) to access the ignition coils.
  2. Disconnect the electrical connectors from the ignition coils.
  3. Use a multimeter to test each coil for resistance; replace any faulty coils.
  4. Replace spark plugs if worn or fouled.
• Tools Required: Socket set, multimeter
• Safety Warnings: Ensure the ignition system is de-energized before working on components.

4. Throttle Body and MAF Sensor Cleaning

• Sub-steps:
  1. Locate and remove the air intake duct to access the throttle body and mass airflow sensor.
  2. Use throttle body cleaner to spray and clean the throttle body, ensuring the plate operates freely.
  3. Clean the mass airflow sensor with MAF sensor cleaner and let it dry before reinstallation.
• Tools Required: Throttle body cleaner, MAF sensor cleaner
• Safety Warnings: Avoid touching the MAF sensor with fingers as oil can damage it.

5. Reconnect and Test

• Reconnect the battery negative terminal.
• Start the engine and monitor for any abnormal behaviors or stalling.