Reduced engine power is something you might see pop up on your instrument panel to warn you of an issue with your engine. But what does reduced engine power mean, and what should you do about it?
Reduced Engine Power signifies that the car has lost some power and isn’t performing as it should. Common cause include reduced flow of fuel and/or air to the engine, clogged catalytic converter, problem with the air intake, or a dirty mass airflow sensor.
Unfortunately, this warning message can indicate a number of problems with your engine. Some may be serious, while others are minor.
The good news is, you can continue to drive with reduced engine power. However, you may have problems accelerating or starting the car.
But keep in mind that your car went into fail-safe mode for a reason. And continuing to drive without getting the vehicle looked at right away could lead to costly repairs later down the road.
Truth is, the reduced engine warning light is meant to give you time to get your car to a mechanic before it breaks down. In any case, when this warning light is on – get your car to a mechanic as soon as possible.
While it’s worrisome when something like this happens to your car, understanding what this fail-safe is and why it occurs will help you figure out how best to deal with the issue.
Let’s dive into exactly what reduced power is, plus some tips for getting back on the road quickly.
What Exactly is Reduced Engine Power Warning?
The Reduced Engine Power warning is a fail-safe system implemented by General Motors. It’s purpose is to warn drivers that there’s something amiss with the vehicle.
As the name suggests, the message on the instrument cluster is notifying you that the engine power is reduced. Additionally, your check engine light may also be on.
Fact is, your engine is armed with an array of sensors that monitor conditions in the engine. When a system failure occurs, the powertrain control module (PCM) will put the vehicle in Reduced Power Mode.
In short, this fail-safe feature helps protect the car from further damage.
What Causes Reduced Power Light to Come on?
When the reduced engine power warning light illuminates, it may indicate a variety of issues. Low fuel level could be to blame, or you might have an overheating problem due to coolant temperatures.
It is also possible that there’s insufficient oil pressure affecting your car’s performance. Or, a clogged catalytic converter due to oil consumption could also be the culprit.
Another possibility is a a faulty throttle actuator control system – common with GM vehicles. Or perhaps something as simple as a dirty mass air flow sensor.
Generally, the cars sensors will detect a problem, then put the vehicle into low power mode. This protects the vehicle from further, more costly damage.
What Happens When Reduced Power Light is on?
Your ability to accelerate will be diminished, putting your car into what’s referred to as “limp mode.”
This mode is a fail safe to protect you from over stressing the engine after a system failure. Potentially causing further damage to the car, or even injury to yourself.
The underlying cause can be a major part failure, or just a minor glitch in the system.
For example, it could be a communication error between the numerous sensors and computers causing the issue.
Whatever the case, your first course of action should be to head to a safe parking spot and contact your mechanic.
They may walk you through the steps to conduct a diagnostic and provide further instructions from there.
Keep in mind, you can still drive in reduced power mode. But it’s best to get the car looked at as soon as possible.
Is it Safe to Drive with Reduced Engine Power?
In most cases it’s safe to drive only a short distance when the reduced power light is on. Because the vehicles computer has put the car into limp home mode to protect the engine.
As a result, the car will have less power when accelerating.
How to Reset a Reduced Engine Power Light
Turn off the car and wait 10 seconds. After 10 seconds, restart the car to see if the reduced engine power light is still illuminated.
If the warning light is no longer illuminated, it means a sensor could be going bad. However, if the light is still illumined, the problem could be mechanical related.
Reduced Engine Power Trouble Codes
Depending on the make and model of your vehicle, certain trouble codes can be stored in its digital brain — otherwise known as the electronic control module (ECM).
These trouble codes can include:
- P0120-P0124 – This code points to issues with the pedal position or throttle position, or the circuit.
- P1125 – These indicates a faulty system or component and may vary depending on the make and model of your vehicle.
- P1518 – This points to a faulty system or bad system component and may vary depending on the make and model of your car.
- P2111 – This code means that the throttle actuator control system is stuck open.
- P2135 – This indicates a problem with the accelerator pedal position (APP), the throttle position (TP) sensor or switch, or the A/B voltage correlation.
If your car has suddenly gone into the dreaded reduced power mode, find the closest local auto parts store. Ask them to run a scan of any error codes, it’s a free service.
Knowing which error code is causing the reduced power will help you determine if it’s safe to continue driving, or needing to call a tow truck.
Reduced Engine Power on your instrument cluster is the last thing you want to see, but rest assured that it’s a failsafe to protect you and your vehicle from harm.
If you see this message pop up, get to a local auto parts store for a quick scan. However, if the car sputters or fails to start, contact your mechanic or roadside assistance right away.
Last Updated on February 1, 2023
Loves anything with a motor and wheels.
Christopher is an internet technology expert and mechanical engineer. When he’s not at the local autocross event, he can often be found working on one of his cars. He loves nothing more than taking something apart and putting it back together again. Email me direct, or learn more about us