Engine Power Reduced: Here’s What You Need To Do

If it appears, it probably means that your vehicle’s computer has discovered an issue with your engine. When your car won’t start, then there could be a problem with your engine. The reduced engine power warning on your dashboard might be flashing red or orange.

Your car’s computer system monitors various aspects of your engine and sends information to the dashboard display. The car’s computer will detect a problem, and alert you with a warning light.

If you are experiencing a reduced engine power warning light on your car, then you should check out this article. It will explain what the warning light means and how to fix it.

what does engine power reduced mean

What Does “Reduced Engine Power” Mean?

The reduced engine power light means that the car has lost some power.

This could be due to a number of reasons, such as a faulty alternator, bad battery, or a problem with the ignition system. If you notice that the engine is running rough, then you should check these things first

Reduced engine power can also mean that the vehicle is losing gas. In order to determine how much gas is left in the tank, check the gauge located near the steering wheel. A full tank indicates about half a gallon of gas remaining.

If the gas gauge shows empty, then the car must stop immediately. Otherwise, the driver risks running out of gas and having trouble getting home safely.

Additionally, if the engine starts making unusual noises such as knocking sounds, this could indicate problems with the pistons. These are usually caused by worn piston rings.

When reduced engine power happens when driving at high speeds, then you need to get off the road immediately. You can also try restarting your car by pressing the brake pedal several times until the engine starts up again.

You should ensure that all the lights in your car work properly. Also, don’t forget to turn off the radio while checking out your car for any loose wires. Do this before trying anything else.

If you have noticed that your car suddenly loses its power, then take note of what caused it. Then, do something about it right away before ending up damaging your car further.

10 Common Causes of “Reduced Engine Power” Message and How to fix it

There are several reasons why the reduced engine power message appears. Here are some common causes and their corresponding fixes:

10 Common Causes of “Reduced Engine Power” Message and How to fix it

1. Low Voltage at Batteries

The most common cause of a reduced engine power warning is when the batteries fail to supply enough energy to keep the engine running.

When the battery dies completely, the engine shuts down immediately. However, if the battery still holds some juice left in it. then the engine will continue to operate until the remaining amount runs out.

How to fix it: Replace dead or weak batteries with new ones.

2. Alternator Failure

An alternator failure causes the engine to shutdown due to a lack of electric current As mentioned earlier, this can happen when there aren’t enough amps being produced by the alternator.

How to fix it: Check whether the alternator belt has slipped. If it does, replace the belt

3. Starter Motor Failure

A failed starter motor prevents the engine from starting. Since the engine requires electricity to function, without any electrical current flowing through the starter motor, the engine cannot begin cranking itself.

How to fix it: Inspect the condition of the starter motor. If it doesn’t seem like it needs replacing, try tightening its bolts.

4. Fuel Pump Failure

A defective fuel pump stops delivering fuel into the carburetor which results in poor performance. This problem occurs because the fuel pump fails to deliver sufficient pressure to push the fuel through the lines.

How to fix it: Replacing a faulty fuel pump may not always solve the problem. In such cases, make sure that all connections between the fuel tank and the fuel filter are tight.

5. Ignition System Problems

Malfunctioning electronic ignition components prevent the engine from firing. There are several causes of this, including blown fuse, loose connections, damaged wires, etc.

How to fix it: Make sure that the spark plugs are properly connected to their respective coils. Also, ensure that they’re clean and dry.

6. Bad Spark Plugs

Poorly performing spark plugs don’t deliver adequate amounts of sparks to ignite the mixture inside the combustion chamber. Hence, the engine does not turn over.

How to fix it: Try changing the spark plug wire connectors. Clean the spark plugs using an air compressor or clean the spark plug holes thoroughly using an old toothbrush. After cleaning them, apply fresh oil on top of each hole.

7. Faulty Wiring Harness

A malfunctioning wiring harness may have caused one or more of the above failures. It’s important to check for these problems before you start your vehicle.

How to fix it: Disconnect the negative terminal of your car’s battery for 30 seconds. Then reconnect it back to the positive terminal. Do this again after 5 minutes. Repeat these steps every time you hear the reduced engine power warning

8. Defective Coil Pack

A defective coil pack usually occurs when the coils become corroded or worn out. The corrosion makes the insulation lose its ability to conduct electricity. Eventually, the entire circuit becomes non-functional.

How to fix it: Remove the cover panel located behind the dashboard. Look at the underside of the hood. You’ll see two rows of four small round terminals. These are the coil packs. They should be replaced once they’ve lost most of their original color. Look for signs of corrosion or wear-and-tear. Repair them accordingly.

9. Other Issues

Some other mechanical fault such as a broken timing belt, cracked head gasket, leaking coolant system, etc., can also lead to a reduced engine power warning. However, if none of the previous issues is found, then there must be something wrong with the ignition system.

How to fix it: Contact a mechanic who specializes in fixing cars. They’ll be able to diagnose the issue and provide solutions.

10. Stuck Throttle Valve

A stuck throttle valve makes it impossible for the driver to control the airflow entering the intake manifold. Consequently, the engine loses power.

How to fix it: Turn off the key switch. Open the hood. Lift up the throttle lever with both hands. Pull it towards yourself until it clicks. Close the hood. Reattach the key switch. Start the vehicle. The engine should now start running smoothly.

If the problem persists after trying to restart the engine manually, then it’s time to take your vehicle to an authorized service center.

Furthermore, if the engine starts turning over but fails to produce much more than idle rpm. then it’ll probably require replacement parts.

Hence, before attempting to jump-start the engine, it would be advisable to disconnect all accessories so that they do not drain the battery unnecessarily. Furthermore, it wouldn’t hurt to remove the key fob from its charging port.

If none of those steps work, then it’s time to call a professional mechanic. They’re equipped with diagnostic tools that allow them to pinpoint exactly what part needs fixing.

Systems That Can Cause Low Engine Power

Low engine power isn’t always caused by faulty parts or components. It can sometimes occur due to other factors such as poor driving habits. Here are some examples of systems that can lead to reduced engine power:

Systems That Can Cause Low Engine Power

Poor fuel quality

If there is no proper mixture between the fuel and air. then the resulting combustion process will not produce adequate energy levels. As a result, the engine will only generate less horsepower. Furthermore, low engine performance may also indicate a lack of oxygen in the exhaust fumes.

This happens because the catalytic converter has failed to convert harmful emissions into harmless ones. Hence, you need to replace this component immediately.

Inadequate air flow

When the amount of oxygen available to burn the fuel inside the cylinders is inadequate, then the engine won’t have enough power to turn over.

This happens because the carburetor doesn’t deliver sufficient amounts of fresh air into the engine.

The intake manifold must provide ample airflow to the cylinders. Otherwise, the engine will struggle to draw in enough oxygen-rich air into the cylinder chambers. In turn, the engine will burn off fewer octane points and thus reduce output.

Excessive Exhaust Back Pressure

When exhaust backpressure increases beyond an acceptable limit, the engine will experience lower performance. For example, if the muffler system becomes clogged with debris, then the engine will suffer because it cannot expel carbon dioxide efficiently.

This results in higher temperatures within the engine which causes damage to vital internal parts. Therefore, it’s important to keep the exhaust pipe free of obstructions at all times.

Improperly Tuned Intake Manifold

A poorly tuned intake manifold can also contribute to low engine power. When the throttle plate closes too quickly, the intake valves open late and allow unburned fuel to enter the chamber. Consequently, the engine produces less torque.

This condition occurs when the intake valve springs don’t close properly. The intake camshaft should rotate faster than the crankshaft for optimal operation. If the timing belt breaks down, then the intake valves will fail to shut completely.

Overheating Issues

As mentioned earlier, overheating issues can prevent your vehicle from generating maximum power. A hot engine requires additional cooling capacity.

Hence, when temperatures rise above normal limits, the engine will run slower. Furthermore, excessive heat can cause premature wear on critical engine components.

To avoid these problems, make sure that your car’s radiator fan works effectively. Also, ensure that the coolant level remains full so that the water pump does its job well.

Finally, check whether any leaks exist around the engine block. These small cracks could be allowing excess oil to escape.

Don’t Panic! Reduced Engine Power Warning FAQs

If you’ve ever had an issue with your car’s engine power, then you know how frustrating it can be. If you’re experiencing reduced engine power, there are a few things you should keep in mind before you panic.

Can I drive with a reduced engine power warning on?

Yes, you can still drive with reduced engine performance. It is only necessary to adjust the air intake system to reduce the amount of air entering the engine.

Furthermore, when driving downhills, you may notice that the vehicle feels sluggish. This problem can be fixed by adjusting the throttle position so that it opens wider.

In addition, some people find that they get better gas mileage while operating their vehicle under reduced engine power.

Driving with reduced engine power is a common misconception among drivers. It’s often assumed that if you’re driving at a lower speed you’ll get better gas mileage. However, this isn’t always true.

Also, driving with reduced engine power is not dangerous, but it is illegal in some countries. Although laws vary widely from one country to another, generally speaking, it is legal to drive at lower speeds when traffic conditions allow.

How much should your RPM be when driving with reduced engine power warning?

The amount of RPM you should be driving at depends on how much power you have left in your engine.

If you have less than 10% of your engine’s capacity, then you should drive at about 50% of your normal RPM.

If you have between 10% and 20% of your engine s capacity, then you can drive at 60% of your normal RPM. and if you have more than 20% of your engine’s capacity, then you should only drive at 70% of your normal RPMs.

How much should your RPM be when driving with reduced engine power warning

What are the symptoms that my car has lost some of its power?

You can tell whether your car has lost some power by looking at the dashboard lights. You’ll see two different types of warnings: one type indicates problems in the electrical system; another type indicates problems with the engine.

It is also possible to tell whether your car is running smoothly by listening to it while it is still off. If you notice any odd sounds coming from the engine, then you need to bring it into an auto repair shop immediately. Otherwise, you risk damaging your vehicle further.

Expert Tip: To determine how much engine power your car has lost, first check its gauges. There should be three separate gauges located near the steering wheel. One gauge measures oil pressure, while the others measure fuel level and water temperature.

A low oil pressure warning light will appear whenever the oil pressure drops too far. You can also use the dipstick to see whether it needs changing.

A low gas tank indicator warns you when the amount of gasoline in the tank falls below a certain point. Use the same method as above to check the gas level.

An overheated radiator may cause the engine to lose some power. Check the thermostat valve and replace it if necessary. Also, ensure that the fan belt is tight enough so that it won’t slip during normal operation.

How long will my engine run without producing any power at all?

It depends on how severe the condition is. If the engine runs fine while idling, then chances are good that it won’t last very long once you step away from the steering wheel.

However, if the engine stalls immediately upon starting, then it could go on for quite some time.

Can I use compressed air instead of gasoline to fill up my tank?

Yes, but make sure that you have plenty of gas available. You may need to add extra amounts depending on how full the tank was prior to filling up.

Will this affect my warranty?

No, since this is just a warning light rather than a defect covered under the manufacturer’s warranty.

Does this mean that something bad happened to my car?

Not necessarily. This simply indicates that the engine wasn’t getting sufficient fuel flow. Therefore, it might still be operating within specifications.

Are these warnings common among cars made today?

Unfortunately, yes. The problem stems from the design of modern engines which require more frequent maintenance as compared to older models.

Will a bad o2 sensor cause reduced engine power?

A bad 02 sensor could cause reduced engine power. If you notice any unusual noises from your car such as a loud clunk, then you should check for a bad 02 sensor.

The 02 sensor is located under the hood, and it measures the amount of oxygen flowing into the engine.

When the 02 sensor fails, it causes the engine to run leaner, which means the air/fuel mixture is too rich. This results in poor fuel economy and increased emissions.

How Much Does it Cost to Fix Reduced Engine Power?

Have you ever own a car or any types of vehicle with engine? If yes, then probably you have already spent a dollar fixing any of its parts, right? But let get to the point, how much does it cost to fix reduced engine power?

This question will only be answered if you know what specific engine part has the problem.

To know the problem, it must undergo first a simple or a comprehensive diagnostic pinpointing of its faulty parts. This diagnostic thing is already part of expenses which may cost you at least 80 to 90 USD. This is just only for knowing what is the problem that reduces your engine power.

The next thing is, after being diagnosed already, it is about time to identify the parts needed to be replaced or managed. Say for example there is a slight problem to the throttle system of your vehicle that is one of the common trouble areas of any types of vehicles.

The price for fixing this part might vary from 30 to 50 USD. Approximately, you area bout to spend for at least a hundred dollars or more, depending again on the kind of repair your vehicle needs.

Can Bad Spark Plugs Cause Reduced Engine Power?

A mechanic holding old broken sparkplugs
A mechanic holding old broken sparkplugs.

Absolutely. Worn-out or defective spark plugs could be the cause of your engine problems. Bad spark plugs can lead to increased engine wear, reduced acceleration and poor fuel economy, so you want to diagnose and repair the problem as soon as possible.

A tell-tale sign of bad spark plugs is when your engine is shuddering or misfiring. The problems may become especially apparent while idling, as at low revs, the spark plugs can “skip a beat” and the engine will struggle to keep spinning. The engine could also surge when accelerating, resulting in jerky bursts of sudden speed instead of a smooth zero-to-sixty.

Rough starts are another a symptom of bad spark plugs, although your should also check the battery and other parts of the ignition system if your main problem is difficulty starting your car.

Fortunately, spark plugs are one of the cheaper parts of a car to get replaced.

Final words

A loss of engine power does not always indicate an issue with the vehicle itself. It could be caused by many different things including faulty sensors or other components. There are several reasons why your engine would suddenly stop working. However, most of them don’t pose much danger to your health.

If you suspect that one of those problems has occurred, contact your local mechanic right away.

Our guide hopefully made it clear to you what happens when your engine loses its power. Any questions you may have about anything we covered here, feel free to ask us!

Good luck!

Avatar photo
About Brock Rangel

Hi, I am Brock, and I am the lead editor/photographer for TheCarColony. I have been a mechanic for over 14 years now, and I am here to spread my car knowledge across the web!