A possiblity until you find another tube is to put some silicone on the cracks. That will seal them up, plus remember the vacuum hose under the tbe that connects to the power steering pump. It is just a bit easier not being turbo charged in finding a leak, but there are a lot of vacuum hoses to check, so the spray is the easiest way to check it out. Even an open EGR valve will mess with the idle.
Russ
