Red Seal Automotive Service Technician Practice Exam

Which of the following is a visible indicator of a fuel leak?

1. Smoky exhaust

2. Strong fuel odor

3. Excessive engine noise

4. Increased fuel consumption

The correct answer is: Strong fuel odor

A strong fuel odor is a clear and direct visible indicator of a fuel leak because it signifies that fuel vapors are escaping from the fuel system. When fuel leaks occur, the liquid fuel can easily evaporate and become airborne, leading to a noticeable smell. This strong odor is often one of the first signs that mechanics or vehicle owners notice, alerting them that there may be a problem with the fuel lines, injectors, or fuel tank. In contrast, while smoky exhaust and excessive engine noise may indicate other engine issues, they do not specifically point to a fuel leak. Increased fuel consumption can occur for various reasons, but it alone does not provide a direct indication of a leak. Therefore, a strong fuel odor is the most reliable immediate indicator of a potential fuel leak.