The car won’t start but has power is undoubtedly one of the most distressing scenarios for any vehicle owner. Imagine getting into your vehicle on a beautiful day, only to discover that it won’t start, even though there’s power.
This situation can be exasperating and disheartening, but with the correct guidance, diagnosing the problem becomes much simpler. This article explains the reasons why your car won’t turn over but has power.
If your car fails to start but still has power, it isn’t fulfilling its primary purpose—transporting you from one location to another.
A dead car battery is a common issue we’ve all likely encountered at some point, preventing the engine from starting. But if your car has power but won’t turn over, it’s clear that the issue isn’t with the alternator or the battery.
In this scenario, it’s essential to investigate other potential issues. This article mainly explains why a car won’t start but has power.
Reasons Why My Car Won’t Start but Has Power
If your car won’t turn over but has power, there may be one or more of the below-given causes:
- Faulty Fuse
- Dead Battery
- Faulty Alternator
- Faulty Starter
- Bad Fuel Pump
- Insufficient Fuel Pressure
- Bad Fuel Injector
- Clogged Fuel Filter
- Faulty Engine Sensor
- Faulty Distributor or Ignition Coil
- Bad Spark Plug
- Dead Key Fob Battery
- Damaged Timing Belt
1) Blown Fuse
First of all, you should check the battery wiring and fuse before replacing the battery, starter motor, or alternator.
If your ignition fuses have blown, a straightforward fuse replacement could be all you need to get the vehicle started again. However, it’s important to investigate and understand the reason for a blown fuse initially.
The wiring harness could also be a potential source if the car won’t start but has power. If there’s a rodent issue in your locality, these pests might be the cause your car isn’t starting. Rodents can quickly chew through a car’s wires, disrupting critical connections.
Even with a perfectly functional battery and starter motor, the loose connections may render these components ineffective. A damaged wire may lead to electrical shorts that might blow a fuse or, more seriously, pose a fire risk. Therefore, it’s crucial to inspect your car’s wiring and ensure no damage has occurred.
2) Dead Battery
If your car won’t turn over but has power, the immediate assumption is not a faulty battery. Although this seems contradictory at first glance, let me clarify. If your vehicle refuses to start, but all the electrical systems are operating, it’s highly unlikely that a dead battery is the cause.
In the case of a dead battery, none of the electrical components will function in the most severe scenarios. If your battery doesn’t have sufficient or low power, you will notice a clear reduction in the performance of the electrical components, such as the lights may be noticeably dim; the vehicle radio won’t turn on, and soon.
In such conditions, it’s important to take into account the age of your battery. A new battery is less likely to fail so soon, but if your battery is over four years old, it might be nearing the end of its life.
If you haven’t used your car for a long time, you should try jump-starting and driving your vehicle for some time. This should charge up the battery, and if it’s still in good shape, restarting the car should be straightforward. If this isn’t the case, you should check the health of your battery by using a multimeter.
Use a multimeter to check the battery voltage—it should be above 12 volts. If it reads lower than 12V, it’s time to replace your battery, and you should be back on the road in no time.
3) Faulty Alternator
If your car won’t start but has power, a faulty alternator may be the reason.
The alternator of your vehicle is one of the crucial components of the car’s electrical system. Its function is to draw power from the engine to recharge the battery while your car is running.
A malfunctioning alternator can prevent the vehicle from starting because if it fails to charge the battery, the battery can deplete its stored energy and eventually die.
If your vehicle’s alternator doesn’t recharge the battery, the electrical components will start to draw power directly from the battery. This process can ultimately drain the battery completely, leaving it unable to supply the starter motor with the large amount of electricity required to start the engine. As a result, the car won’t start even though it has power.
Examining the alternator is a relatively straightforward process. Begin by jump-starting the vehicle, then take a multimeter to check the voltage at the battery terminals. If the voltage on the battery terminals is lower than 12V, your battery might be dead.
However, the key sign to look for is an improvement in voltage as you start your vehicle engine. A functioning alternator should supply a surge of electricity to the battery while the engine is operating. If there’s no change or only a slight increase in voltage, this indicates that your alternator has failed to perform its duty.
Possible alternator problems could include a problem with its coil, which turns the mechanical power of the engine into AC voltage. However, there may be a problem with the Rectifier or Stator, which transforms this AC voltage into DC voltage.
It’s important to remember that diagnosing these issues should be performed by a professional mechanic.
Read More: How to replace and Alternator
4) Faulty Starter
The starter motor of your vehicle is attached to the engine’s crankshaft. It’s the component responsible for turning the crankshaft to initiate the engine’s cycles when you turn the ignition key. If the starter motor fails, this could be the reason your car won’t turn over but has power.
Finding a problem with the starter motor is fairly straightforward. When you turn the ignition switch, the engine should start immediately. Your vehicle starter motor is responsible for engine cranking.
If this motor goes bad, turning the key won’t make a difference. There will be no cranking and no efforts to get the cylinders firing.
To verify that the issue lies with the starter motor, you should first rule out a faulty alternator or dead battery. If these components are functioning correctly and the engine still doesn’t start at all, it’s highly likely the starter motor is the cause of the problem.
If your vehicle has a manual transmission, you can theoretically push-start the car. However, this is not recommended due to safety concerns—it’s also quite a strenuous task. Instead, we suggest towing the vehicle to the local workshop and replace your defective starter motor.
Read More: Starter Motor Working and Parts
5) Bad Fuel Pump
A malfunctioning fuel pump is not typically an issue with most new vehicle models. If you drive your vehicle regularly and properly fill your fuel tank with clean gasoline or diesel, you shouldn’t encounter this problem unless the car was originally equipped with a defective fuel pump.
However, if the vehicle is rather old, or if the quality of the fuel in your zone is not good, dealing with a bad fuel pump could be a troubling reality.
Identifying this issue is relatively straightforward. When you turn your ignition key to the ignition position—before starting the engine—you may notice a humming sound originating from the rear of your car. This noise indicates that your fuel pump is working, ensuring the flow of fuel and preparing it for injection before the car starts.
However, with a bad fuel pump, this process may not occur. In such a situation, your engine won’t receive the fuel according to its requirement, and your car won’t start despite having power.
So, if you turn the ignition key and do not hear the characteristic humming sound from the rear of the car, it could be indicative of a faulty fuel pump.
Read More: Bad Fuel Pump Symptoms and Causes
6) Insufficient Fuel Pressure
While your fuel pump may be operational, what happens if the fuel pressure is still too low?
Blocked fuel lines or fuel rails are the most common causes of low fuel pressure, or there might be a problem with the fuel pump resulting in reduced fuel pressure.
If you find that the fuel pressure is low, it’s best to hand the car over to a mechanic for a more detailed diagnosis. However, bear in mind that these problems are most likely to arise in old vehicle models.
Read More: Function of Fuel Rail
7) Bad Fuel Injector
A bad fuel injector is also one of the possible reasons due to why your car won’t start but has power. For a car with a four-cylinder engine to fail to start, all 4 fuel injectors would need to be dysfunctional. While unlikely, it’s still a possibility.
You may inspect the fuel injector yourself by pressing a screwdriver against each one and listening for a click as the engine cracking. If you hear a click, that particular fuel injector is likely working correctly.
If all your fuel injectors are not working, your next step should be to check the throttle position sensor. Try removing the sensor and turning on the engine. If your engine starts, it means that your throttle position sensor is faulty, and you need to replace it.
Normally, it’s recommended to regularly clean your fuel system as part of your vehicle’s maintenance routine.
Read More: Bad Fuel Injector Symptoms and Causes
8) Clogged Fuel Filter
In some cases, a blocked fuel filter or air filter may prevent your engine from starting. It’s crucial to properly inspect if your fuel filter or air filter is clogged and replace it if necessary.
Additionally, inspect the air tube leading to the engine for any signs of contaminants. If the pathway appears clear, then it should be fine.
9) Faulty Engine Sensor
Your vehicle contains multiple sensors that help the engine to work efficiently. The MAF sensor and MAP sensor are the major engine sensors. These sensors play a vital role in measuring the pressure and volume of the air entering the engine cylinder.
The vehicle computer utilizes the data of these sensors to control the fuel injection rate and ignition timing.
When an engine sensor goes bad, your vehicle computer may receive incorrect readings, leading to car starting issues. To diagnose this, try disconnecting each sensor and starting the engine. If it starts successfully, then it’s recommended to replace the bad sensor.
10) Faulty Distributor or Ignition Coil
The distributor and ignition coil are essential components of your vehicle’s ignition system. If any of these parts fail, your engine will be unable to get the necessary sparks at the right time, resulting in the car won’t turn over but has power.
You can use a multimeter to test the ignition coil and distributor but it’s generally advised to seek the assistance of a trained professional for accurate diagnosis and resolution of the problem.
11) Bad Spark Plug
The spark plug of the vehicle plays a crucial role in igniting the air-fuel mixture in the combustion chamber. Over time, the spark plug may wear out, resulting in a lack of spark to ignite the fuel, causing your car won’t turn start but has power.
Inspecting the spark plugs is a simple process. By removing them, you can examine them for blockages or cracks. If your spark plug’s ceramic area is damaged, it means that its insulation is bad, indicating a broken spark plug. If the tip of your spark plug is blocked with contaminants, it should be replaced.
Read More: Bad Spark Plug Symptoms and Causes
12) Dead Key Fob Battery
In cars with a push-start system, if your engine doesn’t crank as you press the Start button, there are chances that your key fob is experiencing problems or its battery is dead.
A dead key fob battery prevents the Start button from receiving a signal, resulting in the car won’t start despite having power.
To resolve this issue, replace the dead battery in your key fob. You may also utilize a small screwdriver or a coin to open the battery cover, revealing a silver coin or button-shaped battery.
13) Damaged Timing Belt
The timing belt of your vehicle is responsible for synchronizing the rotation of the crankshaft and camshaft. If your timing belt is damaged, the engine will not work efficiently, leading to starting issues.
In case of a bad timing belt, you can notice the starter motor engage but not turn over, or you might even hear a ticking noise from under the hood. While less commonly known, a broken timing belt can occur when the engine is operating and may cause damage to the engine.
It’s important to address any timing belt issues promptly and seek professional assistance, as it involves internal engine components.
Read More: Bad Timing Belt Symptoms and Causes
How to start a car that won’t turn over but has power?
To start a car that won’t turn over, you need to repair or replace one or more of the below-given parts:
- Replace the dead battery
- Replace the faulty alternator
- Replace the blown fuse
- Repair the damaged wiring or loose electrical connections
- Replace the faulty engine sensors
- Replace the bad starter motor
- Replace the bad fuel pump
- Replace the bad spark plug
- Repair or replace the faulty ignition coils
- Replace the faulty ignition switch
- Replace the faulty fuel injector
- Replace or repair the damaged timing belt
FAQ Section
How to start a vehicle with a bad starter?
If you are experiencing difficulties starting your car due to a faulty starter, there are a few troubleshooting steps you can take. Start by ensuring that all the wires connected to your starter are in good condition and securely attached. Check the connectors to make sure they are tight and properly fastened. In some cases, gently tapping the starter with a hammer might help if the internal armature is not making proper contact with the starter motor’s brushes. A light tap can potentially realign the components and restore functionality. However, it is important to exercise caution and use gentle taps to avoid causing further damage.
What sensors can cause a car not to start?
- Camshaft Position Sensor (CMP)
- Crankshaft Position Sensor (CKP)
- Mass Airflow Sensor (MAF)
- Throttle Position Sensor (TPS)
- Coolant Temperature Sensor (CTS)
- Oxygen Sensor (O2)
- MAP Sensor
- Fuel Pressure Sensor (FPS)
- Bad IAT Sensor
What causes a car not to turn over if the battery is good?
- Insufficient fuel pressure
- Faulty fuse
- Dead battery
- Faulty alternator
- Bad fuel pump
- Bad fuel injector
- Faulty starter
- Clogged fuel filter
- Faulty engine sensor
- Faulty distributor or ignition coil
- Dead key fob battery
- Bad spark plug
- Damaged timing belt
What are the most common engine starting problems?
- Poor fuel quality
- Dead battery
- Faulty alternator
- Faulty ignition switch
- Faulty fuel pressure sensor or faulty fuel pump
- Faulty ignition switch or spark plug
- Bad solenoid failure
Can a fuse cause a car not to start?
No, a blown fuse alone typically cannot cause a car not to start. Fuses are designed to protect electrical components and circuits from damage due to excessive current. While a blown fuse can result in specific electrical systems or components not functioning properly, it is unlikely to be the sole cause of a no-start condition in a car.