In this tutorial, we learn how to detect an air leak in a Nitro RC engine. Air leaks damage your engine which will take your tuning and completely void it. Now, take some soapy water and apply it to your engine and anything that is connected in between. Block off one end of the host where you aren't going to blow into. Find where you think the leak is, then make sure you don't have a cracked tank. Next, make sure everything is sealed and apply soapy water. Blow in the other end of the valve and see where the bubbles come out of. From here, you will be able to fix your engine.