​​Reduced Power Warning

The Bulb Check: ​​​​​​​​​Reduced Power Warning

​​​​​​​​​​Indicates Engine Computer has limited engine power output. The ECM has many levels of reduced power depending on what component has failed in its control system.

​Example: If a throttle body is failing the engine will not get the correct mixture of air and fuel. ... The throttle position sensor also controls shifting the gears of a vehicle, which means that a faulty throttle position sensor will prevent a car from changing gears. If this part is failing, the Reduced Power light will trigger.

​When specific faults are detected electronically, the engine control module begins the process of limiting vehicle speed, gear range, and engine power. This can be caused by engine trouble, transmission faults, or even a bad battery.

​​What to Do: ​​​​​​​​​Reduced Power Warning

​​​​​It is important to note that the warning light should be ​taken very seriously any time it is displayed, and continued use of the vehicle may cause severe damage to the drivetrain, or leave driver ​stranded.

​Most newer cars today have anywhere from 60 to 100 sensors and this will increase as they make cars more and more intelligent. However some of the typical things that can cause the Reduced Power Warning Light to come on are not as bad as you think. Some are basic and common sense issues, while others you should take it to a professional for diagnostics and part replacements. 

  • ​Dirty Mass Air Flow Sensor (MAF)
  • ​Dirty Air Filter
  • ​Under-performing Fuel ​Pressure
  • ​Worn Out Catalytic Converter
  • ​Throttle Position Sensor(TPS)
  • ​Coolant Temperature Sensor (CTS)

​​Dirty Mass Air Flow Sensor (MAF)
​This sensor monitors the air flow that is drawn in when the engine is breathing. If the sensor is dirty, the computer will not get the correct information between it and the emissions output and cause the fuel mixture to be incorrect. The solution is to buy a can of MAF cleaner. Do not use carburetor cleaner as that can destroy the sensor. Yo may have to take it loose from the air duct leading to the engine but spray it out.

Dirty Air Filter
A dirty air filter will restrict the air the engine needs. Since the air filter is before the Mass Air Flow Sensor, it can cause the sensor to read incorrectly. Solution is just buy a new air filter.

Under Performing Fuel Pressure
This can be caused by the fuel pump going bad but the first thing you would try is replacing the fuel filter before getting into the time and expense of replacing a fuel pump.

Worn Out Catalytic Converter
If your vehicle has over 150000 miles, change the catalytic converter. The catalytic Converter is part of your exhaust system, it converts dangerous Carbon Monoxide into a more tolerant Carbon Dioxide. There is no fix or repair for a catalytic converter, just have it replaced. 

Throttle Position Sensor (TPS)
This sensor is mounted to the throttle body and monitors how much you are pressing on the gas pedal. If this sensor goes bad, the computer will not correctly tell the fuel injectors and the ignition timing how to properly function. The only solution is to have it replaced.

Coolant Temperature Sensor (CTS)
This temperature sensor is for the computer to monitor the engine temperature so that the computer can adjust the fuel mixture and ignition timing to get peak performance from the engine. If this sensor goes bad, it not only will set off the Reduce Power Warning Light but can also cause the engine to run and start funny. The solution would be to replace this sensor.