Message Engine Power Reduced Duramax (Why And How To Fix)

Modern engines come with modern problems. Technology has been used to upgrade a variety of engines. The trouble is that owners cannot keep up with all the possible error codes or problems created by technology’s upgrades This is one of those problems that take time to figure out how to fix.

This message arrives when your onboard computer, etc., detects a problem. If you travel on a lot of dusty roads, the source can be as simple as a dirty fuel filter. All you need to do is replace the old one with a clean one. Or you are getting air into the fuel supply and priming is needed to fix that source.

To learn more about this issue, just continue to read our article. It explores the topic so you have as many answers as possible. Take a few minutes to see how this important information helps you get out of this mess easily.

Why Does My Diesel Truck Say Engine Power Reduced?


The first thing to do is look at what code is being sent to you. The error code will tell you exactly what is wrong with the engine and why you are getting reduced power.

If your dealer does not help you with this, then you should look for a dealer who will. There have been reports of dealers abdicating their responsibilities by saying they do not know what the problem is. They have their reasons why they do this.

Or they will clear the code in hopes that it will return. However, as usual, the code does not come back until you have left the dealer. There are many reasons why you would get this message on your screen

The trick is to find the part that has broken, failed, or malfunctioned. There are three common parts that produce this code or message. The first is a bad air filter; the second is a bad fuel filter; the third is something is wrong with the gas pedal sensor.

There may be other parts causing this message to be sent but those are the most common ones. If you buy a code checker and clearer device, you do not have to depend on the dealer to find out what is actually wrong.

What Does It Mean When Engine Power Reduced Comes On?


This message simply means that you have a part under the hood that has failed, gotten dirty, or damaged in some way. It could also mean that there is a problem with how the system was designed.

According to one mechanic, he had 5 people within a week come into his shop with the same message and same error code. The code was P0101 and all 5 people were towing trailers on a hot day.

He had the same visits the year before and both times were after periods of extreme heat. The year of all these vehicles was 2009. So there can be a design flaw, a part flaw, or something else.

When you see this message, it means that you are not going to be able to drive at full power until you get the part fixed. This can be a problem as some dealers say they do not know what is wrong and do not fix the problem.

Owners have had to go to independent mechanics to get a resolution for the trouble. It is not a fun situation to be in. When you buy used or have had your truck for a long time, independent mechanics will be your best place to get the problem fixed

What Triggers Reduced Engine Power?


There are several parts that can trigger that message. The ones that are most common will be a dirty air filter, a dirty gas filter or there is a malfunction in your gas pedal sensor.

When these parts go bad, you won’t be able to drive your truck at full speed until you replace them. In some areas, the gas filter costs around $50 which is a high price tag for something that never totally solves the problem.

If the new filters get dirty again, expect to see that message pop up again. Other parts that may trigger this message will be the EGR valve or the air intake valve. If they are dirty, etc., then the reduced speed message will be highlighted and the appropriate action will be taken.

Or, there is an air leak somewhere and the air is getting into your fuel supply. This bad mixture will cause the same problem for you if you do not take care of it right away.

The reason you get this message is that the engine is designed to protect itself and the transmission. Once either get too hot, you will have problems

How do You Fix a Reduced Engine Power?


This will depend on the part that has gone bad or broke. Each repair, although similar in some cases, is not always easy to do or diagnose. Hunting down the bad part may be the hardest part of this task.

1. Throttle or gas pedal- when you get the message that your engine is going to reduce speed mode, this may be one of the prime parts that caused the situation.

You have to make sure the sensor is working, not dirty, and fully functional. If not, then you should replace the sensor. Make sure the throttle works fine as well.

2. Electrical problems- this is one of the harder to find problems but once you do, it is a simple fix for the dealer. They just replace the component that has gone bad. Once replaced, the Duramax engine will reset upon restarting the motor.

3. Filters-- buy an extra one of each just in case. Roads can get dirty and dusty over time and all that dirt and dust seems to find their way to the air and gas filter.

When it does, your air and fuel supply get cut and triggers the message. For the fuel filter, you have the extra problem of how good the fuel is when it is put inside your tank. Contaminants can clog up a filter very quickly.

4. Powertrain Control Module- this part may not have to be replaced. When it is the source for the message and power failure, you need the dealer to duplicate the code.

Once that is done, the Duramax should reset itself and you should be fine.

5. Throttle body- this is a different part and it is found under your hood. There may be debris inside this part and you will have to open it up. However, once you have opened it up, you have to throw away the gasket and replace it with a new one.

Then clean out the part getting rid of all the debris inside. When you are cleaning, do not use any solvent or cleaner with the following ingredient-- Methyl Ethyl Ketone (MEK).

That ingredient can cause damage to other gas components. There are at least 15 steps to cleaning this part and you have to be careful not to damage any component inside of it.

Other sources for the reduce speed message are:

- bad spark plug

- low fuel or clogged fuel line

- cables and coils are loose or have loose connections

- flawed Throttle Actuator Control

- Catalytic Converter is not working right

- low transmission fluid in the transmission control module

- battery is low on power or not connected correctly

Duramax Reduced Engine Power Reset


Some owners have been able to reset their Duramax by unhooking the battery, waiting for a few minutes, and then reconnecting the battery again. However, this does not solve all reset problems.

The same goes for the power module code duplication. It will reset some of the time but other parts may still be bad causing these rest options not to work.

If this is the case for you, you may have to change filters and check the fuel, oil, and transmission fluid lines to make sure they are not clogged. Next would be to check the throttle body for debris, etc.

Also, check the sensor to make sure it is working right. If these options do not work for you, it is best to go to a qualified mechanic and let them reset the engine for you.

Modern engines are not designed for the home mechanic to work on anymore. You may need expert help. Also, different model years may have different procedures to follow.

Some Final Words

When it comes to modern engines, the sky is the limit when it comes to what is wrong. There is a multitude of parts that can fail. When they fail, your truck loses power and you are not going to go anywhere fast.

Instead of trying to DIY the fix yourself, go to a qualified independent mechanic. Dealers are not always reliable nor are they very helpful.

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