Quick question for you experienced guys! I want to do a poor man's leak down test. Please tell me if you think this will work or am I wasting my time. I only have a compression tester, but I do have a small compressor. I want to take the compressor and run some air through the compression testers fitting into the cylinder and listen for where the air is going. However, since cylinder 3 and 4 are the ones that failed the compression test couldn't I stuff the air in one cylinder, place my finger over the other and see if it builds up pressure? At that point it would seem most likely a bad head gasket right?