However, if you're determined to attempt it yourself, here's a general overview of the process. Again, proceed with extreme caution and at your own risk.
What you'll need:
* Refrigerant: You'll need R-134a refrigerant for your 1999 Expedition. This is sold in cans with a hose and gauge. Do not use any other type of refrigerant.
* AC Manifold Gauge Set: This is crucial for monitoring pressure and ensuring proper charging. It connects to the low-side and high-side ports on your AC system.
* Vacuum Pump: This is essential to evacuate the system of air and moisture before charging. Moisture in the system can damage the compressor.
* Leak Detector (optional but highly recommended): This helps find leaks in the system before recharging. A leak will render your recharge attempt useless.
* Safety Glasses and Gloves: Always protect yourself when working with refrigerants.
General Steps (Highly Simplified):
1. Locate Service Ports: Find the low-side and high-side service ports on your AC system. They are usually located near the compressor.
2. Vacuum the System: Connect the vacuum pump to the low-side port and evacuate the system for at least 30 minutes, ideally longer, to remove air and moisture. Monitor the gauge to ensure a good vacuum is achieved.
3. Check for Leaks: Before charging, use a leak detector to check for any leaks in the system. Repair any leaks before proceeding.
4. Charge the System: Connect the refrigerant can to the low-side port and carefully charge the system according to the manufacturer's specifications. Consult your owner's manual or a reputable repair manual for the correct amount of refrigerant for your vehicle. Use the manifold gauge set to monitor the pressure throughout the charging process. The pressure should fall within the specified range for your vehicle's ambient temperature.
5. Test the System: After charging, start the vehicle and run the AC system to check for proper cooling.
Important Considerations:
* Refrigerant is under high pressure and can cause serious injury if mishandled.
* Improper charging can damage the AC compressor and other components.
* Many things can cause AC failure besides low refrigerant; a leak is the most common. A professional can diagnose the problem correctly.
* Even with the correct procedure, improper handling can lead to costly repairs.
Again, this is a simplified and potentially dangerous process. If you lack experience with automotive AC systems, take your vehicle to a qualified professional. The cost of professional repair will likely be much less than the cost of repairing damage caused by improper DIY attempts.
