This weekend I replaced the temperature sending unit in my 1992 FJ80 and to make it easier I removed the belt that runs the smog pump and power steering. After putting everything back together and tightening the belt down I went to start it and it created an extremely loud hissing noise that seems to come from the driver side of the engine compartment. At first I thought it was the smog pump with a bad connection to a line since I did move it but I didn't feel or see any leaks coming from it and I'm now lost as to what it is.