12 Common Reasons Your Car Won't Start
New or used, cars can sometimes disappoint by failing to start. Turning the key or pressing the ignition button and realizing nothing is happening and you won’t be going anywhere is just part of the human experience, but it helps to know what might be causing the problem so you can take the appropriate action. Take a look at some common reasons why you’re stuck and what you can do to get back on the road.
1. The battery is dead.
If you attempt to start your car and don’t see the dashboard lights come on or hear the engine turning over, it’s possible your battery has died. (Weak or non-functioning headlights are another giveaway.) If the car is in a generous mood, it might display the battery symbol, which is a pretty good hint of where the problem lies.
In the olden days, you would just jump-start your car and be on your way. But according to AAA, some modern car manufacturers advise against jump-starts because it could damage sensitive electronics—and it can be dangerous if done incorrectly. All the relevant information for your car—and the correct method to jump-start it if your car can be jump-started—should be in your owner’s manual, and most car manufacturers have a wide range of owner’s manuals on their website if you’ve lost yours. Alternately, you might be able to use a portable car charger that’s approved for your vehicle.
2. The battery connection is bad.
This is less common, but still possible. If your car won’t start, the cable connections on the battery might be bad or loose. Try turning them. If they move, the terminals are loose and need to be tightened. If they show corrosion or are otherwise dirty, they should be cleaned or replaced before being reattached. Since you’re likely going to be dealing with metal tools around a battery it pays to be very careful and know what you’re doing—or just have a professional do it.
3. The alternator is bad.
If you can start the car but it stalls or you’re experiencing interior lights that start out bright and then dim, the alternator could be the culprit. The battery symbol may also appear on the dashboard and you may even notice a burning smell, since the alternator works with belts. There’s no quick fix, so you’ll want an expert to take a look. If it’s bad, it might have also damaged the battery.
4. The car isn’t in park.
A car won’t start if it’s in gear. Check the gear shift to make sure you’re in park or neutral. (Hope that no one is in the car with you when this happens.) If it won’t start in park but will start in neutral or vice versa—or it’s in gear and is starting anyway—it might be a bad neutral safety switch, which can be very dangerous. You'll need the help of a professional.
5. The ignition switch has a problem.
The ignition switch carries power from the battery to the car’s components. If there’s no power to the starter motor or ignition system, you’re stuck. One hint is that you get lights, which means the battery is working, but nothing else. This is another job for a mechanic, but there is a way to try and prevent the problem in the first place. Because the ignition switch is located behind the ignition lock cylinder—the place where you insert your key—having a heavy keychain can put stress on the ignition switch when the key is inserted. Start carrying fewer keys.
6. The key fob battery is dead.
If you have a push button system and nothing happens when you press "Start," it’s possible your key fob could be to blame. The button wants a signal from the key fob before it will work, which it won’t get if the key fob’s battery is dead. Try replacing the fob’s battery. But until then, many car manufacturers have either a physical key hidden in the fob or some form of battery-less identifier.
7. The starter is broken.
The starter does pretty much what the name indicates: It starts the engine when you insert the key or use a key fob. If you hear a clicking noise when trying to start the car, it might be the starter (though dead starters don’t always make the clicking noise). You’ll need a mechanic’s help for this issue, too.
8. The timing belt needs to be replaced.
The timing belt is a rubber strip that rotates the cam and crankshaft in the engine at the proper time. If it fails, the engine won’t run. You may hear a ticking sound coming from under the hood or hear the starter motor engage but not turn over. This is less common than other possible issues, as timing belts typically break while the engine is running (which can be very bad) and some cars now come with chain belts that last longer than the rubber version. Either way, it will require a trip to the repair shop.
9. The fuel filter is clogged.
Fuel filters help with delivering nice, clean fuel from the gas tank to the fuel injectors. Although usually a cause of poor performance, if they get clogged, the car is stuck. Dirty fuel filters can be the result of low-quality fuel or lots of mileage.
10. The distributor rotor and cap are broken.
A distributor is responsible for directing electricity to spark plugs, which ignites the fuel. If the cap isn’t on tightly or the rotor isn’t functioning, the spark won’t travel. The good news? Most newer cars use individual coil packs that replace the distributor. In older cars, a bad cap may lead to noises like tapping or sputtering. Get a pro to replace it.
11. The steering wheel is locked.
If your car’s steering wheel gets stuck in the locked position, it may not allow the car to start. (You really, really want to be able to steer a car in motion.) Don’t yank too hard on the wheel. Instead, use a side-to-side motion with the key in, or use a duplicate key if you can. Your current one may be worn and unable to communicate with the lock tumblers.
12. The car is out of gas.
Sometimes, the solution to a problem is simple. Don’t overlook the fact you might need to fill up your gas tank before hitting the road. And try not to let your tank run low too often. In cold weather, moisture from the air inside the tank can freeze, creating ice that can mean trouble for the engine.