A/C Leak Troubleshooting

[ef330xi]

I have a 2005 330xi, and I'm experiencing warm air from the passenger A/C and slightly cooled A/C on the driver A/C. After searching various BMW websites and YouTube, I found and did a recharge of the system with a small can of R134A. The pressure was below the recommended level based on the outside temp. After this, the A/C did work well on both sides.

However, after 3-4 weeks, I'm back to the same spot. (warm on the passenger side, and slightly cooled on the driver side).

After additional research, I've read it's a good thing to change the Schrader values in both the High and Low pressure sides. I've seen a tool on YouTube that allows this process to be down without discharging the whole system.

Some, here are my questions:
- Can just the values be replaced, or do I need the whole part (64-509-177-577)?
- Is there a tool for replacing this for my car?
- Is there a specific valve needed? Some videos show numerous size values.

- Are there other troubleshooting suggestions? Or, do I need to have the system checked at the dealer .

Thanks in Advance
Ed

[Manolito]

You can get a kit with an ultraviolet flash light and ultraviolet dye that you add to the refrigerant that will help you to locate the leak. Sorry. but I am not familiar with replacing Schrader valves.