The presence of oil around and AC fitting or line is a strong indication of freon leaking. My first step in most auto repairs including auto AC leak diagnosis is to perform a solid visual inspection of the entire system.
Although this is always my first step for diagnosing Freon leaks it is not always effective in finding the problem.
In fact, this visual inspection will only uncover large to extremely large leaks. And by far the most common car AC problem would be small leaks that allow Freon to escape over long periods of time.
To find refrigerant leaks using the fluorescent tracer system, you first have to install the fluorescent dye into the air-conditioning system. Always follow the instructions and do not install too much dye! It can reduce overall system efficiency.
These kits come with an injection device to push the dye into the lines. After circulating it you then put on your yellow glasses and look for traces of the dye and Freon mix leaking out. I have more information on these types of ac leak detection devices.
Working on car AC is dangerous
If you should come in contact with liquid Freon, The best advice is to run the affected area under cool water for 15 minutes and then seek immediate medical attention.
You don't have to be afraid to attempt Diy ac repairs as long as you think it through first and realize the possible complications of your actions.
Example: If you undo a fitting that has 100 psi of Freon pressure, chances for injury are high. If you recover the Freon first and open the fitting with no pressure present in the ac system (confirmed with a connected manifold gauge) injury would be near impossible.
Auto ac Freon leaks can be an expensive repair at specialty shops during peak demand (summer). People with some experience in the driveway can often solve issues causing the ac to blow warm air. I'm a strong believer that it is easier to fix something when you understand how it works.
Find more information about the business of car repairs and the most recent posts on the blog for online auto repair