Reduced Engine Power after Oil Change (Causes and Fixing)

Routine regular maintenance is necessary to keep your car running perfectly. However, timely engine oil changing is more important than performing other service jobs. Reduced engine power after oil change is common when an oil change is not properly done. If you face poor engine performance after changing motor oil, don’t panic. The causes and solutions have been unveiled below in this article.

reduced engine power after oil change

Cause of Reduced Engine Power after Oil Change

Virtually all modern vehicles are fitted with a computer system that triggers a reduced engine power warning signal on the dashboard once engine power declines. This warning simply means something could be wrong with the vehicle’s engine.

Besides the illumination on the dashboard, the car will manifest some malfunctions such as poor acceleration, ineffective gear shifting, etc. The following reasons may be responsible for reduced engine power even after changing oil, such as using wrong engine oil, excess oil or dirty oil filter in the car.

Engine oil with incompatible viscosity

Most vehicles are manufactured with strict recommendations, especially when performing routine maintenance. For examples, some manufacturers recommend a unique engine oil brand with a specific viscosity for their vehicles.

In other words, applying a different engine oil with an incompatible viscosity will automatically affect the engine’s performance. Components like rod bearings, hydraulic lifters, and other metal parts in the engine rely on engine oil for lubrication.

Therefore, an incompatible oil may lead to low oil pressure and fail to provide proper lubrication for the engine parts, resulting in friction between the metal components. When this occurs, the vehicle will suffer several setbacks, including loss of engine power.

Excessive oil in the engine

Too much oil in an engine will do more harm than good to a vehicle. Every engine has a specific recommended quantity of oil to engender optimum performance. Filling the oil beyond the maximum quantity level will result in poor lubrication.

The poor lubrication will further lead to increased friction due to the metal-to-metal contacts between the engine’s components. This can trigger loss of power, poor acceleration, increased temperatures, and smoke coming out of oil cap, engine overheating.

Therefore, sticking to the recommended oil levels when changing your vehicle’s engine oil is essential. Also, if you’re not a DIYer, ensure to contact a professional auto mechanic for your engine oil change to avoid complications.

Bad or dirty oil filter

Professional auto mechanics recommend that it is best to replace the oil filter when performing an engine oil change. The component can become clogged from dirt or debris over time, resulting in poor oil circulation.

Therefore, retaining the existing oil filter may hinder the proper supply of oil to the necessary engine components. This will lead to inadequate lubrication and will result in friction, produce a random ticking noise, and lead to reduced engine power.

Sometimes, a car owner may replace the oil filter with an incompatible product. This can either decrease or increase the oil pressure level, thereby impacting the engine’s performance.

Other Reasons for Reduced Engine Power

Other reasons that may be responsible for reduced engine power include bad oxygen sensor, ECU malfunction, clogged catalytic converter, etc. Let’s see some of them in detail.

Bad oxygen sensor

The oxygen sensor is responsible for monitoring the amount of O2 in a vehicle’s exhaust to send the signal to the computer system for proper air-fuel mixture ratio. Therefore, when this component becomes faulty, it will transmit wrong signals, which can alter engine power.

Clogged catalytic converter

The catalytic converter plays an extremely vital role in neutralizing harmful gaseous pollutants before they are released into the atmosphere via the exhaust pipe. Unfortunately, this component can become clogged over time.

When this happens, the car will not just fail an emission test, it will also experience some engine problems. Sometimes, the dashboard check engine light will accompany the other symptoms.

ECU malfunction

Since the engine control unit (ECU) stands as a central point where a vehicle’s sensors’ signals are sent, a malfunctioning ECU will interpret some signals inaccurately and trigger the wrong function. This can result in adverse performance, including operations that alter vehicle engine power.

How to Fix Reduced Engine Power Mode

The approach to be implemented in fixing engine power mode issue in a vehicle will be determined by the actual cause of the problem. In any case, the following recommendations can help fix reduced engine power issue.

Use the recommended oil

If you’re experiencing engine power reduction and you discover that you’ve mistakenly used a brand of oil with an incompatible viscosity, ensure to drain the oil and replace it with the recommended product as soon as possible.

Sticking to the recommended engine oil by your vehicle’s manufacturer will help you avoid this problem in the first place. So, ensure to overcome the temptation of using any oil brand that comes in handy at the moment when you need to change your car’s engine oil. Always cool your car before changing the oil.

Maintain maximum oil level

Again, if too much oil is responsible for the engine problem you’re currently facing, ensure to restrict the oil level to the marked maximum point when topping off your engine oil.

So, if you’ve mistakenly filled the oil level beyond the ideal quantity, you may want to contact an expert auto technician to drain the oil. Meanwhile, if it’s something you can handle, carefully fix it immediately.

Replace faulty engine-related components

Finally, if you discover that the problem is traceable to a fault other than the engine oil change after proper diagnosis, ensure to fix it appropriately.

For instance, if you find out that the engine problem is caused by a faulty oxygen sensor, clogged catalytic converter, malfunctioning ECU, etc., ensure to replace the components as soon as possible.

Meanwhile, replacing some of these components can be relatively complex; hence, you may have to consult a professional auto technician to handle the job. While some parts, like the catalytic converter, may be expensive, others can be relatively cheap.


Can an oil change cause the car to lose power?

Ideally, changing a car’s engine oil is not supposed to cause the vehicle to lose power, provided you stick to the manufacturer’s recommended oil. In other words, using an incompatible oil brand may alter your engine’s proper performance.

Unfortunately, some vehicle owners wouldn’t mind using any engine oil brand that comes by when they need to do their vehicle maintenance. This can result in unexpected outcomes. 

Can low oil pressure cause reduced engine power?

Of course! Low oil pressure can result in reduced engine power, among other symptoms. In addition, the low oil pressure will automatically trigger friction between moving metal components in the engine, leading to a decline in engine overall performance.

The engine performance decline is characterized by loss of power, reduced fuel economy, noise from moving metal parts, etc. Therefore, you must avoid this occurrence at all costs due to the damage it may cause in the long run.

Is it safe to drive a car with engine power reduced?

Of course not! No matter what, malfunctions that affect a vehicle’s engine power are most likely to cause severe damage in the long run. Therefore, it is not ideal for driving with reduced engine power.

However, the reduced engine power may not affect the car’s locomotion, depending on the cause of the power reduction. So, if you’re experiencing this issue, ensure to contact an expert auto mechanic as soon as possible.

Can bad spark plugs cause reduced engine power?

Yes! Bad spark plugs are also culprits of reduced engine power, among other causes. In addition, a bad spark plug will eventually affect the combustion process, alter engine start, fuel economy, and increase exhaust emissions.

This occurrence will not only affect the engine’s performance, it can also further damage the catalytic converter if the bad spark plug is not replaced as soon as possible.

Will adding oil fix low oil pressure?

Topping off a vehicle’s engine oil level may temporarily fix the low oil pressure. However, if you fail to rectify the actual causes of the problem like oil leaks, burning oil, etc., the oil level will go down again in a matter of time and result in low pressure.

engine oil

Meanwhile, kindly use the manufacturer’s recommended engine oil while you fix the oil leaks and other causes of low oil pressure that you spot. This will help prevent the challenge from reoccurring.


Loss of engine power can be linked to several malfunctions in a vehicle. However, if you’re experiencing symptoms of reduced engine power after oil change, ensure to verify the kind of oil you used. Also, check out the quantity of oil refill.

Once you ascertain the actual cause of the problem in line with any of the issues mentioned above in this article, carefully fix it immediately to avoid further damage to your vehicle’s engine.

Solomon Osuagwu

Osuagwu Solomon is a vetted auto mechanic with over ten years of experience in the garage and five years of experience as a service writer. He prides himself in writing accurate information on professional repair guides, DIY repair guides, buyer’s guides, comparisons, and car reviews. If he’s not in his repair garage, he’s writing automotive blogs to help car owners and fellow mechanics to troubleshoot and proffer solutions to several car problems.

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