A leaking exhaust system can:
- Cause excessive oil use.
- Require your vehicle to have a tune-up sooner than normal.
- Make you drowsy while driving. ✓
- Set grass fires on country roads.
Answer: C. Make you drowsy while driving.
A leaking exhaust system can make you drowsy while driving, because it lets carbon monoxide into the car.
Why this is the answer
The handbook warns that cars produce carbon monoxide, which it calls a deadly gas, and lists driving with a defective muffler or exhaust system among the things you should not do. The point of that warning is to keep carbon monoxide out of the passenger area. Being drowsy is the effect the question is after here, since carbon monoxide building up in a closed car makes a driver sleepy and less fit to drive. If you suspect someone is affected, the handbook says to get them to fresh air and call 911.
Why the other answers are wrong
- A. Cause excessive oil use. — The handbook's exhaust warning is about carbon monoxide gas, not about how much oil the engine uses.
- B. Require your vehicle to have a tune-up sooner than normal. — Nothing in the handbook ties a leaking exhaust to needing a tune-up sooner; the concern is the gas it releases.
- D. Set grass fires on country roads. — The handbook does not mention exhaust systems setting grass fires on country roads.
Remember it
A bad muffler is a gas problem, not a performance problem: it can put carbon monoxide in the cabin with you.