What is a serious consequence of a leaking exhaust system?

A serious consequence of a leaking exhaust system is that it can make you drowsy while driving. This occurs because a leak can allow carbon monoxide, a colorless, odorless gas, to enter the vehicle's cabin. Carbon monoxide can quickly lead to symptoms like headaches, dizziness, confusion, and drowsiness, which can impair a driver's ability to operate the vehicle safely. Prolonged exposure to carbon monoxide can be very dangerous, increasing the risk of accidents due to impaired judgment and reduced alertness.

In contrast, while excessive oil use, needing a quicker tune-up, and setting grass fires can be issues related to vehicle maintenance or issues, they do not directly relate to the immediate health risks associated with a leaking exhaust system in the context of drowsiness and potential harm to the driver and others on the road.