Q: Found one black pipe detached when I opened the hood.

Hi there. The black pipe on your engine is the air intake tube. There are two different tubes. On tube goes to the air box where the engine air filter sits in. The other tube goes to a resonating chamber that helps quieten the air and gives an additional supply of air when stepping on the accelerator. See if the clamp has came off of the hose and put the hose back on with a new clamp. If you need further assistance with the tube coming off under the hood, then seek out a professional, such as one from Your Mechanic, to help you.