why is my Cadillac Escalade T1XX (2021-Present) check engine light on after oil change

Symptoms

• Check engine light illuminated
• Possible oil pressure warning light on the dashboard
• Engine may run roughly or idle inconsistently
• Decreased fuel efficiency
• Unusual engine noises (ticking or knocking)
• Oil leaks observed under the vehicle

Diagnostic Steps

1. Scan the vehicle’s computer system using an OBD-II scanner to retrieve any error codes.
2. Check the engine oil level and quality to ensure it is within the correct range and not contaminated.
3. Inspect the oil filter to ensure it was installed correctly and is not leaking.
4. Examine the oil drain plug for proper torque and signs of leaks.
5. Verify that no electrical connections were disturbed during the oil change.
6. Inspect the air intake and exhaust systems for any disconnections or damage that may have occurred during service.

Solution

1. Preparation

• Gather tools: OBD-II scanner, socket set, torque wrench, oil filter wrench, and a multimeter.
• Ensure the vehicle is parked on a level surface and the engine is cool.
• Disconnect the battery to prevent any electrical shorts.

2. Retrieve and Analyze Error Codes

• Connect the OBD-II scanner to the vehicle’s diagnostic port.
• Turn on the ignition (without starting the engine) and retrieve any stored error codes.
• Document the codes and research their meanings to pinpoint the issue.

3. Check Engine Oil Level and Quality

• Remove the dipstick, wipe it clean, and reinsert it to check the oil level.
• If low, add the recommended oil type as specified in the owner’s manual.
• If oil is dirty or smells burnt, consider performing an oil change again.

4. Inspect Oil Filter and Drain Plug

• Use the oil filter wrench to ensure the oil filter is securely tightened.
• Inspect for any signs of leakage.
• Check the oil drain plug; if loose, tighten it to the manufacturer’s specified torque (typically around 20-25 lb-ft).

5. Reconnect Battery and Clear Codes

• Reconnect the battery terminals.
• Use the OBD-II scanner to clear any error codes from the system.
• Disconnect the scanner once completed.

6. Test Drive

• Take the vehicle for a short test drive to monitor engine performance and check if the check engine light remains off.