Even the most skilled installers can create a boost leak somewhere in the system. This detector fits on the inlet of the turbo. You will use your current clamp for your air intake to connect this detector to the turbo. Pressurize the system all the way on the gauge with an air compressor, and then close the fill valve. The needle should take about 45 seconds to drop down to zero. If it goes faster, you might have a leak. Often times the boost leak will make a loud squeal and then you will have to chase it down with your ear. Putting soap and water in a spray bottle can help you find slow boost leaks. Just spray the solution on boots, intake manifold gaskets and any other connection point to visualize the air leaking.