There are times when my car starts without any problem, while other times it cranks over as usual but won't start. What's the problem?

Chances are if your car starts sometimes and other times it doesn't, the problem lies with the battery. A dead battery is one of the most common reasons why a car won't start, and it can be especially troublesome in cold weather. When starting a car with a bad battery, you may hear a clicking noise that indicates the starter motor is trying to turn the engine over but can't because the battery doesn't have enough power. If this is the case, you'll need to jump-start your car or replace the battery. Another possibility is that your car's alternator isn't charging the battery properly. This can happen if the alternator belt is loose or damaged, causing the alternator to spin too slowly. In this instance, you'll need to tighten or replace the alternator belt. Lastly, a faulty starter motor can also prevent your car from starting. If this is the issue, you'll need to have the starter motor replaced by a professional mechanic.