Question Exhaust system parts should be: Answers Leaking. Rubbing against other parts of the vehicle. Secured tightly. Explanation When inspecting an exhaust system, you should verify that parts of the system are not loose, broken, or missing. The system's parts must be properly mounted and should not be rubbing against moving parts of the vehicle. This questions appears in the following tests: Kentucky Tank Missouri Passenger New Mexico Class B Knowledge Test New Mexico Class B Knowledge Test Utah Class A Knowledge Test Virginia Class A Knowledge Test