Car won't start

When your car won't start it's easy to feel frustrated. Whether you're late for work, or need your car for the school run. A car that won't start brings all your plans to a stop.

We'll take a look through the most common reasons that your car won't start. 

Why won't my car start?

Flat or faulty battery

A flat or faulty battery is one of the most common callouts to the AA.

Listening to the sound your car makes is a good first step to working out what's wrong. If your car makes a rapid clicking sound when you turn the key, a flat or faulty battery could be to blame. It's fairly common for this to happen if you haven't used your car for a while, or if you've left your lights on overnight.

Battery problems are also more likely to happen during the winter. When a battery gets cold it can struggle to hold charge.

You may need to jumpstart the engine using jump leads. But you'll need another car. Only do this if you're confident you know what you're doing, as using jump leads can be dangerous. If the other car battery has charge but yours still won't start, you might need to clean or tighten the connections.

Most batteries need to be replaced after about six years, so it might mean that you need a new one. In this case, it's a good idea to contact a mechanic for their expert opinion. 

Faulty starter motor or fuse

A clicking noise when you try to start your car can also mean a faulty starter motor or fuse. The starter motor is connected to the car's battery and sets the engine in motion when you turn on the ignition.

The most likely cause is a poor wiring connection or faulty solenoids (electromagnets). It's difficult to fix this yourself, so it might be worth taking your car to a mechanic. They'll likely want to check the car's electrical system for faults.

Fuel system problems

Sometimes fuel system problems can be to blame. This is a fairly common reason for your car failing to start, especially in cold weather. Your car needs more fuel to get going when it's cold. And if you're already running low, the engine could have trouble starting.

If a simple top up doesn't fix the problem, there could be an issue with the fuel filter. If your filter is clogged it means that fuel can't reach the engine.

Most manufacturers recommend replacing your fuel filter every two years, or 15,000-20,000 miles. If you're in doubt though, check your car's handbook for guidance.

Ignition system problems

A problem with the ignition system in your car could be the cause of your woes. The ignition switch activates the starter when you turn the key. Over time, the switch can wear out and struggle to start the engine.

Some newer cars start with the push of a button. Your smart key fob sends a coded signal to the button. So if your engine won't recognise your key, the car won't start.

If it's the key fob that's faulty you'll probably also find your central locking system won't work either. If this is the case, you may just need to replace the battery. You may be able to start your car with a dead key fob by holding it against the start button when you press it.

If you think a faulty key fob is the case, it's worth contacting your dealer for help.

Why won't my car start in the cold?

Cold weather is a common culprit for a car not starting.

When your car spends a lot of time in chilly weather, or out in the snow, you might have a frozen fuel line. This happens when water collects in the fuel line. This often happens when your tank is on the empty side. Most mechanics recommend keeping your tank at least half full during winter.

If a frozen fuel line isn't what's stopping your car, it could be damp spark plugs.

If you're unsure, getting help from a mechanic is a good way to work out the problem. It's always a good idea to get any issues thoroughly checked out. They can be dangerous to you and other drivers, and cause you to fail your MOT if they aren't sorted out.

Making sure you take care of your car in cold weather can go a long way. From properly de-icing your windscreen, to parking your car indoors, there's many ways you can look after your vehicle.

Step-by-step guide to diagnosing car starting problems

So now you know the main reasons for a car not starting. Let's go from the top. Follow this step-by-step guide to working out why your car won't start:

1. Checking the battery

You can check your car battery by using a voltmeter, checking the battery's size, or looking for a bad smell.

A rotten egg smell can indicate vented gas and released sulfuric gas from the battery. This can harm other parts of your engine. If your battery's case is bulging, the cells could be about to rupture. This can be a fire hazard so if this is the case, you'll need a new battery.

You can also see if the check engine light shows up on the dashboard. This may mean your battery's power is low and you might want to get it tested.

2. Inspecting the starter motor and fuse

To check the starter motor and fuse you should consider:

• Is nothing happening when you start the ignition? Is the engine not turning over?
• Is there smoke coming out from under the bonnet? This is a sign that your starter fuse has blown.

Can you see visible damage to your car's fuse box? It's not a good idea to try to check this yourself however, as it can be dangerous. If in doubt, get a trained mechanic to take a look.

3. Identifying fuel system issues

Check the engine light. This is a key indicator of fuel system problems, so is your first warning sign that things aren't right.

You should also check the noise and smell of your car. Smelling gasoline in and around your car can indicate a leak or other issues. A failing fuel pump may also make a high-pitched whining or humming noise from your fuel tank area.

If you've been able to drive your car recently, you may have noticed a reduction in fuel economy. This is how far a car can travel on a certain amount of fuel. If you've had to fill up your tank more often than usual, there might be a fuel system issue.

4. Troubleshooting the ignition system

Troubleshooting your ignition system is relatively easy, but you should always be careful.

Check your vehicle's starter to make sure it's working properly. If your starter is making a grinding or clicking noise, it might mean it's failing.

You can also use a multimeter to make sure it's getting enough voltage to function. A multimeter is a handheld device that measures multiple electrical properties. It can be used to measure voltage, current, and resistance. They can allow quick and accurate measurements, so they're a good way of checking your car.

If this is okay, you'll want to check if your dashboard lights come on when you turn on the ignition. If they don't come on, this is a sign that your ignition switch is faulty.

Finally, test your spark plugs to make sure they're in good condition. You can use a spark tester to check for sparks. You'll want to replace any spark plugs that have become worn or damaged.

How to start your car if it's not starting? - Jump start

A jump start is a useful way to start a car with a flat battery. But it can cause damage to your vehicle if not done correctly. It's not recommended to try to jump start your car yourself. It's best to call a trained mechanic. If you do need to jump start your car, it's crucial you put your own safety first.

The AA outlines instructions below on how to safely jump start your car:

You'll need:

1. A pair of working jump leads
2. A pair of rubber work gloves
3. The car with the flat battery positioned so that jump leads can easily reach the battery
4. Another vehicle with a fully charged battery (avoid using a hybrid or electric car as this can cause damage)

Before you start, make sure to check the jump leads and the car's battery. Here's how to keep yourself and the environment safe:

• Never try to jump start a battery that looks damaged or is leaking.
• Make sure the jump leads aren't damaged.
• If the jump leads start to get hot while you're using them, stop.
• Before you start, remove scarves, ties, or any clothing that could get caught in the moving engine parts.
• Don't let any metal objects touch the car batteries. This can cause a spark and even cause the battery to explode. Make sure you remove rings, watches, and bracelets before you start.
• Never smoke or let naked flames anywhere near the batteries.
• Don't remove the jump leads while the car engines are running as this can seriously damage the cars' electronics.

Jump starting the car

If you've found someone with a car and they're willing to help, make sure the car has a fully charged battery. Their car will also need to have the same voltage as your car (usually 12 volts).

1. Line up both cars. Without the cars touching, make sure they're parked so that the batteries are within easy reach to one another. Keep the handbrakes on and ignitions off.
2. Connect the red jump lead. Use the red jump lead to connect the working battery's positive terminal to the flat battery's positive terminal. Make sure the ends of the red and black leads don't touch as this can create sparks and damage the cars.
3. Connect the black jump lead. Next, take the black jump lead and attach it to the negative terminal on the working battery. Then attach the other end to an earthing point. (the unpainted metal on the engine block or chassis). Keep well away from the flat battery and fuel system. 
4. Start the other car. Make sure both engines are off and wait 3 minutes. Then start the working car's engine and let it run for 1 minute.
5. Start your car. Turn on the engine in the car with the flat battery.
6. Let both cars run. Slightly press the accelerator to raise the engine speed. Aim to maintain an engine speed of about 1500-2000 RPM. This ensures the alternator generates enough power to provide a stronger charge to the dead battery.
7. Turn off and disconnect. Turn off both engines and carefully disconnect the leads in the reverse order to the way they were connected. Make sure the leads aren't touching either car, or each other, as you remove them. 
8. Restart your car. Now for the moment of truth, try turning your keys in the ignition to see if your car will start.

If your car still won't start this probably means there's a more serious problem. It's a good idea to seek professional help at this stage. A trained mechanic can help you work out the issue.

When to call for help: Breakdown cover

If nothing seems to be working, you may want to call for help.

The costs of a breakdown service can be expensive, so getting breakdown covercan be worth considering. This can give you peace of mind if you're ever in the position where your car won't start.

You may also want to add at home breakdown cover on your policy. This is for when you're stuck at home when your car won't start.

If you ever find yourself in a serious car breakdown that puts you in immediate danger, call 999.

If your vehicle was built after April 2018, it should have an SOS button. This is usually found near the top of the windscreen or on the steering wheel. Only use this button if you're in a serious situation like a medical emergency or crash. Or if you witness an incident that requires emergency services. 

Tips to prevent car starting issues in the future

So, now you know some of the possible reasons for a car that won't start. But how do you stop this from happening in the future?

Here are a few top tips to reduce the risk of car starting issues:

• Avoid short trips. When you make short trips you don't allow your engine to reach its operating temperature. This can limit battery charging.
• Park indoors. We've looked at the ways that cold weather can play havoc on your car. Parking in a garage or carport can help prevent battery problems and other common issues.
• Check your battery. Batteries are the most common reason for a car that won't start, so it makes sense to look after them. Regularly check the batteries for corrosion and clean it off so the battery can work properly. Batteries typically last 5-6 years, but you should be on the lookout for a poorly performing battery. You can try trickle charging your battery if you don't use your car very often, or make lots of short trips.
• Change your fuel filter. Changing the filter can prevent it from getting clogged and stopping fuel reaching the engine. Consult your vehicle handbook to check how often you should be changing your fuel filter.
• Regular car maintenance. Regular car maintenance and oil changes can prolong your car's lifespan and help stop engine damage. You should also maintain proper coolant levels, regularly inspect belts and hoses, and keep your air filter clean.
• Practice good driving habits. Overloading your car, frequent braking, rapid acceleration, and engine idling can increase wear on the engine and brakes.

Using common sense goes a long way when prolonging the life of your engine and other car components. It's always worth checking your vehicle handbook if you're ever unsure about something.

Making sure you're aware of the common reasons a car won't start will go a long way. So next time you're having car trouble, don't panic. Go through the step by step guide, and if in doubt, call a mechanic. 

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