Car is Losing Power

If you’ve noticed that your cars losing power when you’re trying to accelerate, it could be a sign of a bigger problem – not just that your car isn’t using as much power. The sooner you’re able to diagnose this problem, the better. What you don’t want is the problem being bigger than you thought and you have to visit the mechanic for a repair. The longer you leave it, the more of a chance that you’ll have to spend money on a repair because a symptom like this can be a problem with the engine. If you feel that your car hasn’t got much power as it used to have, you need to check the reasons why.


When you notice that your car is losing power, there are a few reasons why it may have and some of them will require a repair while others won’t. One thing that can come on when you’re experiencing this problem is the check engine light coming on. If the check engine light comes on when you feel the car losing power when you accelerate, then it’s a sign that there’s a problem.

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The check engine light doesn’t usually come on but when it starts to flash, it can signal a deeper problem with your car. The tough thing about using the check engine light to signify a problem is that it could come on for other reasons as well so it’s best that you group the check engine light with other problems as well.

If you want to know for sure that there’s a cause for this problem, you should use a professional OBD2 diagnostics tool (View on Amazon). When there’s a problem in your car, a signal is sent to a diagnostics unit and this is stored as an error code. An OBD2 scanner will allow you to diagnose these error codes and find out what they mean – this will allow you to know what’s causing your car to slow down. If you use a normal standard OBD2 diagnostics tool, then it might misdiagnose the problem and or it won’t be able to tell you the meaning of the error code, it’ll only tell you what it is – this will force you to go to owner’s manual to look it up.

Low Compression – in the combustion chamber, there is compression going on and this allows the air fuel mixture to be ignited. The air needs to be compressed for this to work and if it isn’t compressed correctly, it’ll mess up the combustion process and this will result in your car losing power and slowing down. If the compression is low, then the engine won’t be able to ignite the air fuel mixture so the car will lose power. If the compression isn’t right in your engine, you’ll need to get this checked out as it’s a problem. Usually, it’s because the fuel filter is clogged.

Clogged Fuel Filter – If your fuel filter isn’t in the right condition, the right condition of fuel won’t be able to get into the combustion chamber. The purpose of the fuel filter is to screen the fuel for any impurities so it can’t get into the combustion chamber and disrupt the air fuel mixture. Once a bad air-fuel mixture is sparked, then the piston won’t be able to move up and down as much and this will stop the crankshaft from turning as much which is why you feel like your cars losing power.

Misfiring – if you notice that your car isn’t performing like it should do when your acceleration, it could be because of a misfire. There are pistons in your engine, and they move up and down when there’s an explosion in the cylinder. When the piston goes down, the cylinder fills up with the air fuel mixture and when they go back up again, the air-fuel mixture is compressed at a high pressure. When the pistons move, this causes the cylinders to move and this turns the crankshaft which turns the wheels for the car to move.

When the engine misfires, then the cylinder has failed to fire, and this would be caused by the air-fuel mixture getting interrupted. When the cylinder fails to fire, the cylinders won’t have as much power as before, therefore the engine will lose power. When there’s a misfire, you’re also going to feel a jerk in the car – this jerk is caused by the engine juddering when the cylinder has failed to fire.

Clogged Exhaust Pipe – the exhaust pipe is part of the exhaust system and it’s where the muffler and the catalytic converter are housed. The catalytic converter is able to use catalytic substances to remove the toxic gases from the emissions. For example, carbon monoxide is a converter to CO2 and water which is what exists the exhaust pipe. The nitrogen oxides and the hydrocarbons are removed using the precious metals in the car converter.

The muffler is meant to decrease how much does the car makes. If either the exhaust pipe or the cat converter gets clogged, this can cause the vehicle to slow down because the engine is weakened. In this case, the catalytic converter needs to be unclogged because it can affect the performance of the engine. The catalytic converter can be cleaned and removed of its deposits by driving over a long period at a high speed – this will cause the cat converter to get hot and this will force it to burn off the carbon deposits that have formed.

Bad Valve Seal or Piston Rings – if the valve seal or piston rings have worn off, then the compression inside the combustion chamber can be reduced and this will cause the engine to lose power and it won’t work the same way. As mentioned before, the air needs to be at the right pressure for the air-fuel mixture to be ignited.

Wrong air-fuel mixture – the air and fuel is let is by the IAT and the fuel pump and the PCM is what make the correct ratio. If other components in the car are giving the PCM the wrong signals, then it means that the cylinders won’t be firing therefore the engine will lose power. The correct air-fuel mixture needs to be present for the engine to keep running at the same power as it used to.

Camshaft Position Sensor Malfunction – if the camshaft position sensor has malfunctioned, then the engine will lose power. The camshaft position sensor is meant to gather information about the camshaft speed of the vehicle, and it’s sent to the electronic control module. This module exists in most vehicle and once the camshaft speed is sent to the ECM, then the fuel injection and the ignition will be times based on this information. However, if the camshaft sensor malfunctions then it won’t be able to send the information to the ECM and this will cause the engine to lose power.

Worn Out Spark Plugs – your spark plugs are what ignites the air fuel mixture inside the combustion chamber, and this is what allows the air fuel mixture to move up and down. The spark plugs use the electricity from the ignition relay and this is then used to spark the air and fuel. If the spark plugs are worn out due to natural wear and poor maintenance, then the air fuel mixture won’t ignition and this will cause the engine to lose power. The spark plugs will be to be replaced because these are a crucial part of the combustion process and without them, the engine won’t be able to function.

Dirty Fuel Injectors – if the fuel injectors are dirty, this can prevent fuel from getting to the combustion chamber. Even if the fuel gets in, it could have impurities if the filter is clogged. The fuel needs to enter the combustion chamber so that it can mix with the compressed air and it can be ignited. If the fuel doesn’t get ignited, then the engine will lose power.

Blocked Fuel or Air Intake – if the fuel or air intake is blocked, this means that the fuel won’t be able to get into the combustion chamber to be ignited by the spark plugs. This means that the explosion won’t happen in the combustion chamber and therefore the pistons can’t move. This block can interrupt the combustion cycle causing the engine to lose power. You may also feel the car jerking when this happens. If either of these are blocked, then the check engine light might come on and this will help you diagnose it.

Accumulated Moisture – if too much moisture has been gathering in the distributor cap, this will cause the engine to lose power and you may feel the engine jerk because of a misfire. When the car is left in the cold weather, then air will condense, and this will build up moisture in the distributor cap. This is why you shouldn’t leave your vehicle parked out in the cold because moisture will build up in areas of your car.

You Treat Your Car Like Shit – If you fail to look after components in your car, you shouldn’t be surprised when you notice problems. Maintaining your vehicle is a crucial process that needs to be done by every car owner and it prevents you from experiencing a lot of problems. Failure to look after just one component can cause a knock on effect and this can be felt in other areas of the car. Maintaining your car will result in you spending less money at the dealership because of well you look after your car.

If you want to avoid engine problems or other issues and save $100s of dollars that you’ll spend at the auto repair shop, you’ll need to service your vehicle often – you can use our mechanic-rated Auto Maintenance and Repair Manual to do this. It’s basically what mechanics use to go through your vehicle to check if there are any problems that need fixing. As soon as they notice the most minor problem, they’ll ask you to fork out some money even though it’s a problem you can fix yourself in minutes – the manual will teach you how to maintain your vehicle every few thousand miles and it’ll teach you how to fix minor problems that mechanics will ask you to pay for; saving you money in the long run.

A lot of our readers have the Auto Maintenance and Repair Manual printed on their garage wall and 92% of them haven’t visited the auto repair shop in the last year because they know what to do to avoid problems. All it takes is giving your vehicle a little attention every few thousand miles and you’ll never spend money at the workshop again.

Dirty Air Filter – if the air filter is dirty, then the air that’s coming into the combustion chamber will either be dirty or there will be no air getting through. If no good quality air is getting through, this will interrupt the air fuel mixture and it might cause a misfire. The right quality air needs to be coming into the combustion chamber through the air filter. If the quality of air is bad and this gets into the combustion chamber, it can cause the car to lose power and jerk.

Bad Transmission Control Module – if you have an automatic transmission and you notice that your car loses power every time the transmission changes gear, you might have a faulty transmission control module. If the transmission control module has problems, or there’s a problem with the solenoid that allows the gears to change smoothly using transmission fluid, then the gear shifts can be unpredictable, and this will cause the engine to lose power.

Weak Fuel Pump – if the fuel pump that gets fuel from the gas tank to the engine is weak, this can prevent the fuel from getting to the engine. The fuel pump makes sure that the fuel is being delivered at the right pressure so that it can meet the engine’s fuel demands. If these demands aren’t met, then the engine will have limited performance.