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Home/Cars/GMC/Sierra/T1XX (2019-Present)/why does my GMC Sierra T1XX (2019-Present) check engine light keep coming on

why does my GMC Sierra T1XX (2019-Present) check engine light keep coming on

GMC Sierra T1XX (2019-Present)

Error Codes
Severity: mediumDifficulty: medium2-4 hours
3 min read
502 words

Problem Statement

Learn how to diagnose and fix the recurring check engine light issue in GMC Sierra T1XX (2019-Present). Step-by-step guide with diagnostic procedures.

Affected Component
Engine
Estimated Time
2-4 hours

Safety Warnings

  • ⚠Disconnect the battery before working on electrical systems.
  • ⚠Allow the engine to cool before inspecting the exhaust system.

Symptoms

  • •Check engine light illuminated
  • •Reduced engine power
  • •Rough engine idle
  • •Increased fuel consumption
  • •Engine stalling during acceleration

Diagnostic Steps

  1. 1Scan for error codes using an OBD-II scanner to identify specific trouble codes.
  2. 2Check the fuel cap for proper sealing and any signs of wear or damage.
  3. 3Inspect the air intake system for leaks or blockages.
  4. 4Examine the exhaust system for any signs of damage or leaks.
  5. 5Test the battery and alternator voltage to ensure proper electrical supply.
  6. 6Inspect ignition components, including spark plugs and ignition coils.

Solution

Solution

1. Preparation

  • Gather necessary tools and parts.
  • Disconnect the battery to ensure safety during the repair.
  • Allow the engine to cool if it has been running.

2. Addressing Trouble Codes

  • Use the OBD-II scanner to read the trouble codes.
  • Research the specific codes to determine the affected system or component.
  • Clear the codes and see if they return after a short test drive.

3. Inspect and Repair Fuel System

  • Fuel Cap Check:
    • Remove and inspect the fuel cap for cracks or damage.
    • Replace if necessary.
  • Fuel Lines:
    • Inspect fuel lines for leaks or damage.
    • Replace any damaged lines.

4. Air Intake System

  • Check Air Filter:
    • Remove the air filter and inspect for dirt or blockage.
    • Replace the air filter if it is dirty.
  • Inspect Intake Hoses:
    • Check for cracks or loose connections in the intake hoses.
    • Replace any damaged hoses.

5. Exhaust System Inspection

  • Visual Inspection:
    • Inspect the exhaust for rust, holes, or loose clamps.
    • Repair or replace any damaged sections.
  • Oxygen Sensors:
    • Check and test the oxygen sensors for proper function.
    • Replace any faulty sensors.

6. Ignition System Maintenance

  • Spark Plugs:
    • Remove and inspect spark plugs for wear or carbon buildup.
    • Replace with OEM specifications if necessary.
  • Ignition Coils:
    • Test ignition coils for proper resistance.
    • Replace any coils that are out of specification.

Verification

After completing the repair, verify that the issue has been resolved:

  • ✓Test the affected component to ensure it functions correctly
  • ✓Check for any error codes or warning lights
  • ✓Monitor the vehicle for a few days to ensure the issue does not recur

Prevention Tips

To prevent this issue from occurring again:

  • •Follow the manufacturer's recommended maintenance schedule
  • •Address warning signs early before they develop into major issues
  • •Use quality parts and fluids recommended for your vehicle
  • •Keep detailed records of all repairs and maintenance

Tools & Equipment Required

  • •OBD-II scanner
  • •Basic socket set
  • •Torque wrench
  • •Multimeter
  • •Screwdrivers

Parts Required

  • •Fuel cap (if damaged)
  • •Air filter
  • •Spark plugs
  • •Oxygen sensors (if faulty)

Additional Information

Affected Component
Engine
Estimated Time
2-4 hours
Difficulty
medium
Severity
medium
Tools Required
5 items
Parts Required
4 items

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