2003 Buick Regal Owner's Manual - Page 96
2003 Buick Regal Manual
Page 96 highlights
Igine Exh ust @ Engine exhaust can kill.It contains the gas carbon monoxide (CO), which you can't see or smell. It can cause unconsciousness and death. You might have exhaust coming inif: Your exhaust system sounds strange or different. Your vehicle gets rusty underneath. Your vehicle was damaged in a collision. CAUTION: (Continued) Your vehicle was damaged when driving over high points on the road or over road debris. Repairs weren't done correctly. Your vehicle or exhaust system had been modified improperly. If you ever suspect exhaust is coming into your vehicle: Drive it only with all the windows down to blow out any CO; and Have your vehicle fixed immediately. 2-29