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​What Does Engine Power Reduced Mean?

Mar 14th 2023

Check Engine Light Dashboard Warning

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Engine Power Reduced is a warning light on the dashboard that turns on when the engine is running low on power. Acceleration will be diminished and your speed may decrease because the engine isn’t receiving enough fuel and/or air. Diesel engines need highly pressurized air and fuel to produce power. They use a long list of various sensors, filters, and tubes that deliver the fuel to the combustion chamber.

The light can come on for any number of reasons, and some of these areas are easier to solve than others. It’s a sign that something is wrong under the hood and the problem should be addressed as soon as possible by finding the underlying cause. Learn how to deal with this problem to protect your engine from further damage.

Diesel Truck Engine Maintenance


What Should I Do When the Engine Power Reduced Light Comes On?

You should visit a mechanic or search online to find out why the light is on. If you have experience fixing diesel engines, you should be able to fix the issue yourself. Use an electric OBD2 scanner to pinpoint the cause of the problem. It should produce an error code. Research the code online or by checking your user’s manual to see what this code means. If you don’t have a scanner, you can test specific parts and sensors to see if they are working properly. Most of the time the issue tends to be minor, such as a loose cable or frayed wire, but it can also mean a crucial component isn’t working properly.

Is It Safe to Drive with the Engine Power Reduced Light On?

You can drive with the Engine Power Reduced light on, but you should head home or to the nearest mechanic to fix the issue right away to avoid further damaging the engine. Experts say that it may not be safe to drive with the light on if the engine is at risk of seizing or catching on fire. There’s simply no way to be sure without investigating the issue. Not being able to accelerate can be a real hazard on the road. You might get rear-ended, slow down traffic, or have trouble driving up hills.

What Causes the Engine Power Reduced Light to Turn On?

Diesel engines require large quantities of high-quality oil. This essential fluid lubricates parts and components to reduce wear and tear. It also helps deliver the pressurized fuel to the combustion chamber via the fuel injectors. Bad oil or not enough oil can cause the Engine Power Reduced light to turn on. The oil may also be overheated, which compromises its ability to lubricate parts of the engine. You may need to replace the engine oil cooler if you recently changed the oil and are still running into problems.

Stock Up on Diesel Parts

Mechanic Repairing Truck


There could also be an issue with the battery, which powers all the electrical components in the vehicle, including the fuel pressure sensor, oxygen sensor, and oil pressure sensor. Check the battery wires and connection ports. Excess dirt, debris, and rust can reduce power as well. Inspect the various connections, gaskets, and seals for damage. Clean the inside of the engine regularly to prevent buildup. Both the air or fuel filter could also be clogged, which will prevent fuel and air from flowing to the engine. Clean or replace the filters as needed.

These problems tend to be more common on older engines and those that do a lot of hauling. Short trips, heavy loads and poor maintenance can all degrade aspects of the engine. They tend to be dirtier and have less reliable parts than newer models. Be sure to replace the various components of your engine as they age to keep your vehicle running strong. Diesel trucks tend to be some of the most durable vehicles on the road, but they aren’t invincible and will deteriorate over time. Learn how long diesel engines last to see if yours is on its way out.

You should be able to accelerate and maintain your speed when driving. Avoid driving with the Engine Power Reduced light on to protect the damage from additional damage and use these maintenance tips to make the problem go away.