i just installed apexi dual intakes in my 93 fd and when i give it gas it makes a loud howling,gurgling sound i know when you install intakes it suppose to make a sucking sound but this is scary loud icould just slightly press on the gas and that sound is heard but when warmed up after driven for about 5 to 10 min noise is no longer heard could someone explain to me what causes that noise..

 

it's from the warm up thingy...the hose at the back of the Intake Manifold.