1. Open the hood of your Audi A4.
2. Locate the engine, which is typically covered by an engine cover.
3. Remove the engine cover to expose the engine components.
4. Look for the crankshaft pulley, which is located at the front of the engine.
5. The CKP sensor is usually mounted near the crankshaft pulley, either on the side or behind it.
6. The CKP sensor is typically a small, cylindrical device with a wire connector attached to it.
7. You may need to consult the vehicle's service manual or repair guide for the exact location of the CKP sensor in your specific Audi A4 model.
Note: The CKP sensor may be located in a different location depending on the specific engine type and year of your Audi A4. It is always a good idea to refer to the vehicle's service manual or repair guide to ensure accuracy and avoid any potential issues.