Many of us rely on our cars to get to the places we need to be, so it would be a big inconvenience when our car won’t start in the morning. Other than the battery, your car might not start because the starter motor isn’t working properly. We’ll be discussing bad starter symptoms, how to diagnose a car that won’t start, and replacement cost should you need a new starter.
- How a Car Starter Motor Works
- Bad Starter Symptoms
- Testing a Car Starter
- Jumpstarting a Bad Starter
- Replacement Costs
How Does a Car Starter Motor Work?
A car starter is used to rotate or crank your engine by providing torque. An electric starter has a solenoid attached to it, which takes the electricity from your battery to power the motor and crank your engine. When you turn your ignition key, the starter motor will start by drawing electricity, engaging the flywheel, and turning your engine. This begins the intake process where your engine takes in air and fuel into the cylinders. Then, the engine starts to compress the air and fuel inside the cylinder in preparation for the combustion process, which ignites the fuel and air mixture.
Once the combustion process has started, your engine will run on its own and no longer needs the starter motor. There are several types of starter motors, which are electric, hydraulic, and pneumatic. Most cars use an electric starter motor, while hydraulic and pneumatic starters are often reserved for larger engines such as gas turbine engines and diesel engines in trucks and generators.
You can learn more about how starter motor works in the video below:
Bad Starter Symptoms to Lookout For
A stater motor typically lasts for 100,000 – 150,000 miles, which means it won’t break anytime soon if you have a new car. However, it doesn’t hurt to look out for the symptoms, so you can tell early if the motor starts to go bad. This way, you can replace it before it fails completely, avoiding your car not starting at an inconvenient time.
1. Grinding Noise
This is a common bad starter symptom if there’s an issue with the starter’s pinion gear. As explained in the video above, the starter motor has a pinion gear that engages with your engine’s flywheel to start the engine. If the gear is worn out or not engaging properly, then it can produce a grinding noise. The noise is similar to the grinding noise you would hear if you were to accidentally turn your key again when your engine is running. Keep in mind we don’t recommend you doing this to find out what it sounds like, as it could damage the starter motor.
If you hear this grinding noise every time you start the car, you should take your car in for repairs. Leaving it unfixed may cause more serious damage to your engine and flywheel.
Freewheeling is also a common bad starter symptom if there’s an issue with the pinion gear. This happens when the pinion gear in your starter motor does not engage with your flywheel properly. As a result, all you will hear is a whining noise as your starter motor spins. When this happens, your car won’t crank at all because the electric motor isn’t engaging with your engine’s flywheel.
3. Starter stays on after the engine starts
As we all know, once your engine is on, you should release the key from the ‘Start’ position. This will then discontinue the power to the starter motor and turning it off. However, if your starter motor keeps running on its own, then it’s likely you have an issue with the solenoid. In this case, the solenoid is welded together in the closed position and keeps powering your electric motor, as if you were still starting the car.
If this happens, you should turn off your car immediately. Leaving your car turned on will cause serious damage to the starter motor and your engine’s flywheel.
4. Trouble starting the car
If your engine cranks but won’t turn on properly, then you likely have other issues often related to the ignition system. However, if you try to start your car but the engine doesn’t turn, and then you try it once again and it works, then it’s likely you have a problem with the starter relay.
The starter relay is like an on and off switch for the starter motor. When you turn the ignition key, it will send electricity to the starter motor system. If the relay is damaged then it won’t send that signal, resulting in your car not starting at all. You can sometimes hear clicking noises as you turn the key if you have a damaged relay.
5. Smoke from your car
This is a less common bad starter symptom, but it could happen. Smoke coming from your starter motor means that it has overheated. It’s usually a sign that too much power is being drawn through the electrical supply, which is often an electrical connection problem. It can also happen when the starter has been operating for too long, but this usually only happens when you’ve tried turning on the car over and over again with no success, overheating the motor.
In any case, smoke coming from your engine is never a good sign and you should give your car a rest and then tow it to the nearest repair shop.
Diagnosing a Car That Won’t Start
Now you know bad starter symptoms, but what if your car won’t start and you can’t tell what’s causing it? Most of the time, a car that won’t start is caused by a flat battery. However, there are other possible reasons that your car won’t start. Before we get into how to test a starter motor, let’s diagnose why your car isn’t starting by learning the symptoms:
1. Flat Battery
If your car won’t start because of a flat battery, you will likely see the following symptoms:
- A low whining or clicking sound as you try to start the car.
- Your engine turns or cranks but only very slightly, meaning the starter motor isn’t getting enough electricity from the battery.
- If your battery is really old and completely dead, then you might not see any lights turn on on the dashboard and other electric components won’t work.
If this is the case, you can simply jumpstart your car and you can be on your way to the nearest auto shop to get a new battery.
2. Bad Alternator
An alternator is an electrical generator that converts mechanical energy to electrical energy. In simpler terms, it takes power from your engine, turns it into electricity, and then feeds it back to your car’s battery. They’re not essential in starting a car, which is why a car with a bad alternator can often still start its engine.
However, a bad alternator means that it won’t be able to feed the battery with the necessary amount of electricity. As a result, your car will be consuming more electricity than it is making. This means your battery will go flat much quicker, as it isn’t getting the amount of electricity it needs. If you can start the car but then it dies and you can’t start it again, then it’s likely you have an alternator issue. You might also notice your dashboard lights and headlights flickering as you try to start the car.
If you suspect you have a bad alternator, try jumpstarting the car to turn it on. Once it’s on, turn off all electrical components, this includes the headlights, radio, and air-conditioning. By doing this, your car will be using less electricity from the battery and it should have enough for you to drive it to the nearest repair shop.
Needless to say, you should only do this during a clear day as you won’t be able to turn on your headlights and windscreen wipers. It’s risky, but it could save you from having to spend money on a towing service.
3. Bad Starter Motor
A car with a bad starter motor usually won’t turn or crank at all. You will often hear a click and your car’s electric components are fine, but your engine won’t crank when you turn the key. Other times, if there’s an issue with the pinion gear, or you will hear is either a grinding noise or the whining noise of a freewheeling starter motor as mentioned in the bad starter symptom section.
4. Ignition and Other Engine Problems
Your car might not start because of a variety of reasons with the engine itself, most commonly with the ignition system. Here are the common symptoms:
- Your car cranks just fine but it won’t turn on and run by itself.
- All electric components are working fine.
If you see the symptoms above, you could be facing ignition problems. This can be caused by either faulty spark plugs or ignition coils. When either of them goes bad, your ignition system won’t be able to create enough spark that your engine needs in order to ignite the fuel and air mixture inside your cylinders to start the combustion process. As a result, your engine can crank, but without the ignition then your car won’t run.
These symptoms might also indicate that your car isn’t getting enough fuel to burn. In which case, there’s an issue with the fuel system. Other possible reasons include a faulty air intake system and a blown head gasket. Whatever the cause, if your car cranks just fine but it still won’t start, then you’re facing an issue with the engine, not the starter motor system.
Bad Starter Symptoms: How to Test a Starter
If you’re experiencing the bad starter symptoms and you suspect it’s the starter motor that’s causing your car not to start, you can do the following steps to test your starter motor. You will need a voltmeter to test your starter and battery, which you can buy for around $45. Or you can borrow it from someone you know if you don’t feel like spending the money.
1. Locate the Starter Motor and Solenoid
First, you will have to locate your starter and solenoid in your engine bay:
- Open your engine’s hood.
- The starter is usually found at the back of your engine, sitting low down. It often sits where your engine meets the transmission.
- Most starter motors have a long cylinder shape with a smaller cylinder sitting on top or on the side of it. This smaller cylinder contains the starter solenoid.
- You will see two different terminals sticking out on one side of the solenoid cylinder. A battery from your car’s battery will typically connect with the upper terminal.
2. Listen for a Clicking Noise
Once you’ve located the starter motor, ask someone else to start your engine as you listen to the starter to diagnose it. The next course of action will depend on the clicking noises you hear from your car:
If You Hear a Repeated Click
If you hear a repeated click from your stater motor, then you can assume it’s working as it should. The clicking noise means the solenoid is transferring electricity, but it’s not enough to crank the car. When it’s not getting enough electricity, the system will make a repeated clicking noise as it repeatedly tries to crank the engine.
In this case, what you should do next is check the battery with a voltmeter and see if it has enough charge. Your battery should have between 12.4 – 12.9 volts, if it’s below that, then the problem lies with your car’s battery. In which case, you can jumpstart the car with jumper cables but the battery will still need to be changed for the car to turn on next time.
If You Hear a Single Click or No Clicks at All
If you only hear a single click or there are no clicks at all, it can also mean your solenoid is fine but the battery is not powerful enough to even power the solenoid. Be sure to check if your battery has the appropriate charge, if it does then it probably means your starter solenoid is faulty. In which case, here’s how you can test the current resistance to check the starter solenoid:
3. Checking the Starter Solenoid
Before doing this or indeed any of the steps above, be sure to remain clear of any moving part of your engine and work in a dry environment to avoid injuries. Now, if you suspect your starter solenoid is faulty, here’s how to check the current resistance:
- Place the positive lead from the voltmeter on the lower terminal of the solenoid. Then, place the negative lead on the upper terminal.
- As you’re doing the first step, have someone else turn the ignition key. Ensure that the leads are firmly touching or attached to the solenoid’s terminals to get an accurate reading.
- Pay attention to the voltage drop that is shown on the voltmeter, you should see a drop of 0.5 volts.
If the drop is less than 0.5 volts, then that means there’s a problem with the solenoid. Meanwhile, if the drop is higher than 0.5 volts then there might be a problem with the connection, such as a crimped line from the battery to the solenoid.
These tests can be complicated and quite dangerous to perform on. If you’re not sure about your own skills, then you can simply take the car to a repair shop and ask a mechanic to do the diagnosis. You can also watch the video below to learn more about how to troubleshoot a car starter:
Can You Jumpstart a Car with a Bad Starter Motor?
While not as straightforward as jumping a car with a dead battery, it is possible to jumpstart a car with a bad starter. There are several methods you can try, and while they may sound weird, they might just work. This can be quite useful if you just need to start the car and get it to the repair shop without the help of a tow truck. Before that, you should check your car for a couple of things:
- Be sure to check your car’s electrical connection, making sure that the cables are in good condition and nothing is loose. A loose fit on your battery’s or starter’s connection may not be able to deliver enough power to start the car. A damaged cable may also affect your starter motor.
- Check for corrosion on your battery connections. If you do spot corrosion, you can clean them with baking soda. Simply sprinkle enough baking soda to cover the connection, and pour a couple of tablespoons of water. Afterward, scrub the terminals with a stiff brush to clean them. Finally, rinse with water to clean them, and be sure to let them dry completely.
After checking for the things above, here are some methods on how to jumpstart a car with a bad starter motor:
1. Hammer Time
Quite literally, tap the starter with a hammer. The starter motor might not be working because it has hit a dead spot. If so, tapping the outer housing with a hammer may force it back into functioning. Scotty Kilmer explains quite well how this method works:
It doesn’t have to be a hammer, any piece of metal will do. Also, if your starter motor is difficult to reach, you can use a long pry bar instead to tap it. Just remember that a light tap should be enough, and no need to really tap it with force.
2. Bypass the Relay
Your car might not start because the starter motor isn’t getting the electricity it needed. If this is the case, you can use a screwdriver to create an electrical connection. Place the screwdriver to touch both the positive starter terminal and the starter solenoid terminal. This will bypass the starter relay and can sometimes start the car, provided the problem was a relay issue in the first place.
3. Push Start the Car
If all else fails and you have a manual transmission, then it’s time to push start the car. Ideally, you will need a couple of people to push your car as you sit inside and control it. To do this, put your car in either first or second gear and hold down your clutch while you’re being pushed. Once you’ve reached 5 – 10 mph, let go of the clutch. This should rotate your engine and will hopefully make it run. If you’ve tried this a couple of times with no success, then we recommend stopping and simply tow your car to a repair shop to get it fixed.
Keep in mind that all of the methods above are a temporary solution. Even if you manage to start the car, we recommend immediately taking it to a repair shop to replace or fix the problem as necessary.
Bad Starter Symptoms: Replacement Cost
Okay, now you know the bad starter symptoms and how to diagnose them. But how about the replacement cost? Well, the cost to replace a car’s starter motor will vary depending on your car’s make and model. To give you a rough estimate, most cars will cost you around $180 – $300 for a starter motor kit, excluding the labor cost. Needless to say, if you have a luxury or exotic car it will cost you more. For example, a starter motor kit for some Mercedes-Benz models is anywhere between $400 – $800. As for the labor cost, it’s usually between $50 – $100 per hour.
Keep in mind that these are rough estimates and just for your starter motor. If your flywheel has been damaged, it can lead to more repairs and higher costs. Which could bring your total repair cost to around $1500, depending on your car make and model. This is why you shouldn’t ignore grinding noises when you start the car, as they could damage your flywheel.
Bad Starter Symptoms: Conclusion
The starter motor is used to crank your engine to turn it on. It draws power from your battery, cranks the engine, and once the combustion process starts, your engine will run on its own. If your starter motor isn’t working, then your car won’t be able to start. By learning the bad starter symptoms, you should be able to tell if your starter motor is going bad. You should replace or repair your starter motor if necessary, so you won’t have to deal with a car that won’t start.
If you hear a grinding or whining noise when you start the car, be sure to check that as well. A grinding noise is never a good sign and can cause further and more expensive damage.