AC Compressor Replacement - 2007-2012 Nissan Altima - How To Fix AC System

Introduction

This tutorial will guide you through the process of replacing the AC compressor on a 2007-2012 Nissan Altima. A faulty AC compressor can lead to poor cooling performance, and replacing it can save you money when done yourself. We’ll cover essential steps, tools required, and tips to ensure a successful replacement.

Step 1: Diagnose the AC Issue

• Ensure the engine is off.
• Attempt to spin the AC compressor shaft:
  • If the shaft spins freely, the compressor may be fine, but the clutch could be faulty.
  • If the shaft is locked, the compressor needs replacement.
• Consider replacing the expansion valve and receiver dryer at the same time to ensure optimal performance.

Step 2: Prepare for Compressor Removal

• Before starting, evacuate the refrigerant from the system.
  • This should be done at a local shop to avoid environmental hazards.
• If your compressor is leaking, you may skip this step if there's no refrigerant left.

Step 3: Remove the Air Duct Assembly

• Disconnect the air duct assembly for better access:
  • This will allow you to reach the compressor and associated bolts easily.

Step 4: Disconnect the AC Lines

• Locate the high and low pressure lines on the compressor:
  • Remove the two 10 mm bolts securing these lines.
  • Disconnect the lines and cover the openings with rags or tape to prevent moisture ingress.

Step 5: Access the Compressor from Underneath

• Lift the car if necessary for better access.
• Remove the splash cover by taking out all plastic push clips.
• On the passenger side:
  • Remove the wheel and splash cover.
  • Unclip and move the power-steering line out of the way.

Step 6: Remove the Drive Belt

• Release the tensioner and remove the drive belt.

Step 7: Remove the Old Compressor

• Unscrew two 12 mm bolts from the bottom and two from the top of the compressor.
• Use plastic caps to cover the openings of the old compressor to avoid oil spills.
• Rotate the old compressor 90 degrees to remove it.

Step 8: Prepare the New Compressor

• Fill the new AC compressor with the appropriate amount of lubricating oil:
  • Check the information sticker under the hood for the correct oil quantity.
  • If the new compressor is pre-filled, skip this step.
• Lubricate the new O-rings with oil before inserting them into the compressor.

Step 9: Install the New Compressor

• Secure the new compressor in place by:
  • Attaching the refrigerant lines and tightening the 10 mm bolts.
  • Plugging in the electrical connector.

Step 10: Reassemble the Components

• Reinstall the drive belt following the instructions in another tutorial if needed.
• Reattach the air duct assembly.

Conclusion

By following these steps, you can successfully replace the AC compressor in your 2007-2012 Nissan Altima. Remember to check for leaks after installation and recharge the system with refrigerant as needed. If you have further questions or need assistance, consider reaching out to a certified mechanic. Happy DIYing!