Car Won’t Start But the Battery Is Good? Causes & Solutions

There is nothing more heart-dropping than being late for work and rushing out the door, only to find out that your car won’t start. Your initial instinct is to call a friend to give you a jump, but then you remember that you just had a new battery put in your car, and the dome light and radio immediately turn on when you turn the ignition, so it is clear that there is power. So why won’t the car start?

Most likely, the issue has something to do with problems in the fuel or ignition systems. There are a number of reasons besides a bad battery that a car won’t start.

Although reasons other than a lousy battery are likely to result in a more costly repair, failure to start does not mean that your car is cooked. In fact, there are even a few clever tricks for getting your car started when jumping will not help. Read on to find out more about why a car with a good battery won’t start and how you can possibly get it firing to get it to the mechanic.

Why Won’t My Car Start But Battery Is Good?

When your battery is good but your car won’t start, you are most likely dealing with an issue in the fuel or ignition systems.

However, before you completely write off the battery, you need to check a couple of things, as it is possible that even with a good battery, electricity is still the issue.

Make sure that the battery terminals are not dirty or corroded. Once they are clean, it can be helpful to add a gel lubricant to enhance conductivity.

Then, check that the battery cables are well connected to the correct terminals.

If both of these items check out, you are getting power to the car’s interior, but you are still not able to start the car, then battery is clearly not the issue, and you are likely dealing with one of the following seven problems.

Fuel Issues

In a best-case scenario, your car is not starting because there is insufficient fuel.

Although it takes very little fuel to start most cars, if you completely pegged your car out before parking, then insufficient fuel may be the culprit. Get a gas can, try adding a little fuel to your tank, and give it another try.

In addition to insufficient fuel, there is a chance that your gas has gone bad. Gas will degrade and begin to lose its combustibility after six months.

Therefore, if your car has been sitting for a long time between starts, then you may be dealing with bad gas. In most cases, mixing fresh gas in with the old gas will produce enough combustibility to start the car (although the car may run rough until all of the bad gas is burned off). However, if the gas is really old, you may need to siphon out the bad gas before adding new fuel.

Faulty Starter

Although adding a little fresh gas would be the ideal solution, it is a long shot that it will solve your problem. Most likely, the problem is a bit more serious, with a faulty starter being at the top of probable issues.

The starter’s job is to initiate the engine and get the car running. The starter relay transmits power to the starter motor to do its job. Therefore, if either the relay or motor go bad, then the engine won’t crank and the car will not start.

Some common symptoms of a faulty starter include:

  • Engine won’t turn over – Your interior lights come on, but nothing happens when you turn the ignition.
  • Whirring sound – Some say that clicking is a symptom of a weak starter, but that can also be a symptom of a weak battery. However, a low whirring or whining sound is an indication that the starter is trying, but the motor is too weak to turn over the engine.
  • Intermittent starting issues – If your car won’t start, you leave it sitting for a while, and then come back and it starts fine, then this is a pretty clear indication that the starter relay is losing its ability to transmit a consistent signal.
  • Smoke – You continue to attempt to start it, but the electrical can overload and become too hot, resulting in smoke from a blown fuse or short circuit.

Starters will wear out over time. If your car is more than 10 years old and still on its original starter, then it is perfectly reasonable to need a starter replacement. This timeframe may be expedited in cold regions where the starter has to work a little harder to get the car going in the morning.

Bad Ignition Switch

Sometimes referred to as the starter switch or start switch, the ignition switch is responsible for activating the vehicle’s main electrical systems. A telltale sign of a bad ignition switch is when you turn the key and nothing at all happens–even from the car’s interior electrical components.

However, this can be difficult to distinguish from a battery or starter issue. As a result, the following symptoms are typically unique to a failed ignition switch:

  • Key won’t turn – There are four positions of the ignition switch: 1) lock, 2) accessory, 3) on, and 4) start. When you turn the key and cannot access all of these positions, it is likely due to a bad ignition switch.
  • No noise at all – With a bad starter, you will usually hear some kind of noise indicating that it is attempting to do its job. The ignition switch is all or nothing, so when it fails, you won’t hear any clicking, grinding, or whirring.

Like the starter, it is normal for the ignition switch to wear out over time, making it a common repair in older vehicles.

Clogged Fuel Filter

As mentioned, it does not require a lot of fuel to ignite the engine. However, it does require some, and if fuel cannot properly reach the engine at ignition time, your car may not start.

A common reason for this may be a clogged fuel filter. Fuel filters will become dirty from debris and oxidation over time, and it is recommended that they be changed every 20,000 miles. If you are well past this timeframe and your car won’t start, the fuel filter may be blocking the path to the engine.

Bad Fuel Pump

Much more serious than a clogged fuel filter, a failed fuel pump is one of the nightmare scenarios for a car that will not start, as most fuel pump replacements cost well over $500.

Located in the gas tank, the fuel pump’s job is just like it sounds. It pumps fuel from the gas tank, through the fuel lines, and to the engine.

While the issue is serious, it can actually be pretty easy for an amateur to diagnose a failed fuel pump. When you turn your ignition to “on” and the fuel pump is working correctly, you should hear a faint whirring that lasts between 1-2 seconds. This sound is the fuel pump sending gasoline to the engine.

Therefore, if you turn your key to “on” and cannot discern this sound, it is likely that the fuel pump has failed, and no spark will happen when trying to start your car.

Shot Timing Belt

A functioning timing belt is one of the most critical elements of a properly functioning engine. It guarantees that the engine’s valves open and close at the proper intervals so that the valves and pistons never touch, ensuring stable combustion. Like the fuel pump, a timing belt replacement can be one of the most expensive car repairs (assuming the engine is not already shot).

Clearly, a bad timing belt would prevent the combustion required for ignition, as the timing belt is necessary for turning over the engine. However, the timing belt is more likely to fail while the engine is running, so this is an unlikely – albeit very serious – cause of failure to start.

If you look under the hood and notice a significant oil leak near the engine, this may indicate a busted timing belt. 

Weak Ignition Coil

The ignition coil transfers a battery’s voltage into an electric spark. When the ignition coil becomes old or damaged, it will not be powerful enough to accomplish this task. You can use a multimeter to test the current running through the ignition coil. You will likely need to get a reading of 12,000 volts or more to indicate that the ignition coil is strong enough.

When diagnosing a weak engine coil, it is also helpful to think back to the last time your vehicle was running. Did you notice any engine misfires? This would feel like your vehicle was surging during acceleration. Did you notice a rough idle? This would make it seem like your car was about to die while sitting at a stoplight.

Both of these are extremely common symptoms of a weak ignition coil, so if you had noticed either of them prior to your car not starting, then an ignition coil replacement is likely necessary.

What to Do If Your Car Won’t Start But the Battery Works

If the battery in your car is good, then getting a jumpstart obviously won’t do anything for you. While it is likely that you will need the help of a trained professional, there are a few tricks you should try prior to giving up hope and calling for a tow truck.

Add Some Gas

Even though insufficient or degraded gas may be a longshot behind your ignition issues, it is so simple that it is worth a try, especially if your car has been sitting for a long time between starts.

Smack the Starter

After the battery, a failed starter is the most likely culprit of a car that won’t start. If you have a screwdriver, try tapping on your starter motor.

If the electrical contacts within the starter get stuck, tapping on the starter can free them, allowing you to start your car and get it to the mechanic for a starter replacement.

Shift the Car to Neutral

With your foot on the brake, shift the car to neutral and try to start the car. If this does not work, return it to “park” and try again.

Sometimes, shifting your car can reestablish contact within the transmission range selector (neutral safety switch), allowing better current flow to help ignite the engine.

Tap the Fuel Tank

Try tapping on the fuel tank several times. If a bad fuel pump is the cause of your dead car, tapping the fuel tank can jar the fuel pump motor, sometimes creating enough of a “reset” to get your car started one last time.

Trick the Computer

A vacuum leak or faltering temperature sensor can sometimes lead to an air/fuel mixture that is too lean to start a cold engine.

Try pushing on the gas pedal halfway and starting the car. This will tell the computer to add more fuel, creating a more desirable air/fuel mixture for generating combustion. This obviously is not a long term solution either, but it will hopefully get your engine started so you can take the car to the mechanic yourself without towing it.

Good Battery But Car Won’t Start: The Bottom Line

When the battery on your car is good but it will not start, you are likely dealing with some sort of issue in the fuel or ignition systems. Some common causes may include inadequate fuel, a faulty starter, a bad ignition switch, a clogged fuel filter, a bad fuel pump, a shot timing belt, or a weak ignition coil.

Although a jumpstart is not a remedy to any of these issues, with some of them likely to require a costly repair, be sure to try one of the simple tricks listed above to get your car started and on the road to the mechanic!

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