Do you currently have car insurance? Insurance is mandatory to drive in California Yes I have insurance. But please show me your best quotes. No, please help me find the best insurance. Question A broken exhaust system can: Answers Let poisonous fumes into the cab. Improve fuel efficiency. Make steering more difficult. Explanation Defects in an exhaust system are very dangerous because they can cause poisonous fumes to enter the cab or sleeper berth. Take a FREE Practice Test Now This questions appears in the following tests: Tennessee Knowledge Test Class A ,