After adding more brake fluid, I noticed a small rubber hose near the battery and air filter not connected to anything. It’s in the perfect position to attach to a random bolt behind the battery. None of my car friends nor a friend that works at Discount Auto could figure out what it does or what it’s supposed to attach to. I tried attaching it to the bolt and the car ran fine. After the car runs, if the hose is detached it makes a long hissing noise so it’s definitely a vacuum tube of some kind. No check engine light has ever come on. The car is a 2011 Mitsubishi Lancer DE 2.0L 4 cylinder.
Last edited by Nikegolfer54; 04-06-2019 at 06:58 PM.