The vacuum system provides a lower atmospheric pressure and basically transforms a car engine into a huge pump that sucks air, mixes it with fuel, and expels it along with combustion gases. Even light damage to one of those vacuum hoses can cause all kinds of performance problems, such as rough idle to an engine that won’t start. If you are having these issues, it might be time to replace those old hoses. This plastic hose has an inner diameter of 2.3mm, is black in color, and arrives in an 8 foot section that can be cut down to size.
