Which of these is NOT a typical symptom of alternator failure?

Strong engine performance is not a typical symptom of alternator failure because the alternator primarily powers the vehicle's electrical systems and charges the battery while the engine is running. When an alternator fails, it leads to insufficient power for electrical components, which results in symptoms such as battery drain, dimming headlights, and warning lights on the dashboard. Strong engine performance indicates that the engine is functioning well, which is not representative of an alternator failure scenario. In fact, a well-performing engine may still be operating normally despite electrical issues stemming from a failing alternator.