Why Does My Range Rover Say Reduced Engine Performance?

Reduced engine performance means your Range Rover engine is not performing at its full capacity and can be caused by various reasons, such as a malfunctioning sensor, a clogged air filter, or a problem with the vehicle’s electronic control module.

Fear not! 9 times out of 10, a faulty sensor will throw this error up as it’s a safety mechanism to protect the engine, which then the ECM sends a message to the engine to lower power.

As a Range Rover Sport owner, I was devastated when I first saw the warning message that said “reduced engine performance” appear on my dashboard. I knew that this wasn’t good, but I wasn’t sure what it meant or what I needed to do to fix it.

After some research and a visit to my mechanic, I learned that various factors can cause reduced engine performance and that it’s important to understand what it means, what causes it, and thankfully it’s an easy fix most of the time!

This fault is very similar to the Range Rover restricted performance error message – the only difference is, the restricted performance is for the newer Ranger Rover models. The reduced engine performance is for older Range Rover models before 2010.

What models are affected?

Symptoms and most likely causes of reduced engine performance

Reduced engine performance can be indicated by warning messages on the dashboard, such as “reduced engine power”, “check engine”, or simply an obvious lack of power from the engine.
Other symptoms can include a decrease in power and acceleration, a rough-running engine, or a check engine light that is on.
The most likely causes of reduced engine performance include a malfunctioning sensor, a clogged air filter, or a problem with the Range Rover’s electronic control module.

Buying guide: Best Land Rover OBD2 scanner tools

Can it be fixed without a mechanic?

In many cases, this issue can be fixed without the help of a mechanic. However, it will require some knowledge of car mechanics and the right tools.

Parts you’ll need

If the issue is caused by a malfunctioning sensor, you will need to replace the sensor with a new one.
If the issue is caused by a clogged air filter, you will need to replace the air filter.
If the issue is caused by a problem with the vehicle’s electronic control module, you may need to replace the module or have it reprogrammed.

Tools you’ll need

A socket set and a ratchet
A new air filter or sensor (depending on the cause of the issue)
A scan tool (if the issue is caused by a problem with the electronic control module)

How to fix your Range Rover depending on the diagnosis

First, check the air filter and replace it if it is clogged or too dirty to be cleaned.
If the air filter is not the issue, check the mass air flow sensor and replace it if it is malfunctioning.
If the sensor is not the issue, use an OBD scanner to check for codes related to the electronic control module and take the necessary steps to fix any issues or other codes that are found.
Once the sensor or air filter is replaced, or the electronic control module is fixed, the reduced engine performance warning should no longer appear.
If none of the above has fixed the error message, check out the other alternative causes below and take the Range Rover to your local garage for further diagnosis.

Potential other alternative causes

A malfunctioning throttle body

A malfunctioning throttle body can cause reduced engine performance by preventing the engine from receiving the proper amount of air, leading to a decrease in power and acceleration.

A clogged exhaust system

A clogged exhaust system can also cause reduced engine performance by restricting the flow of exhaust gases, which can lead to a decrease in power and acceleration.

A problem with the fuel system

A problem with the fuel system, such as a clogged fuel filter or a malfunctioning fuel injector, or faulty fuel pump, can also cause reduced engine performance by preventing the engine from receiving the proper amount of fuel, which can lead to a decrease in power and acceleration. In all these cases, the engine will not be able to produce the power it should which then reduces engine performance.

What OBD codes show reduced engine performance on a Range Rover?

Possible OBD codes for reduced engine performance on a Range Rover include these many codes:

P0100: Mass Air Flow Circuit Malfunction
P0101: Mass Air Flow Circuit Range/Performance
P0102: Mass Air Flow Circuit Low Input
P0103: Mass Air Flow Circuit High Input
P0104: Mass Air Flow Circuit Intermittent
P0171: Fuel Trim System Lean (Bank 1)
P0172: Fuel Trim System Rich (Bank 1)
P0300: Random/Multiple Cylinder Misfire Detected
P0301: Cylinder 1 Misfire Detected
P0302: Cylinder 2 Misfire Detected
P0303: Cylinder 3 Misfire Detected
P0304: Cylinder 4 Misfire Detected
P0305: Cylinder 5 Misfire Detected
P0306: Cylinder 6 Misfire Detected
P1101: Throttle Actuator Control Motor Circuit Malfunction
P1111: Throttle Actuator Control Motor Circuit Range/Performance
P1112: Throttle Actuator Control Motor Circuit Low
P1113: Throttle Actuator Control Motor Circuit High
P1114: Throttle Actuator Control Motor Circuit Intermittent
P1300: Ignition Coil Circuit Malfunction
P1301: Ignition Coil Circuit Malfunction (Cylinder 1)
P1302: Ignition Coil Circuit Malfunction (Cylinder 2)
P1303: Ignition Coil Circuit Malfunction (Cylinder 3)
P1304: Ignition Coil Circuit Malfunction (Cylinder 4)
P1305: Ignition Coil Circuit Malfunction (Cylinder 5)
P1306: Ignition Coil Circuit Malfunction (Cylinder 6)
P1550: Throttle Actuator Control Motor Relay Circuit Malfunction
P1551: Throttle Actuator Control Motor Relay Circuit Range/Performance
P1552: Throttle Actuator Control Motor Relay Circuit Low
P1553: Throttle Actuator Control Motor Relay Circuit High
P1554: Throttle Actuator Control Motor Relay Circuit Intermittent

The Range Rover has tonnes of sensors, probably more than you could ever imagine. You are best plugging the OBD scanner in, and finding the code, and you can verify the error code on our Range Rover OBD code list.

FAQs

Is it OK to drive with reduced engine performance?

No, it is not recommended to drive with reduced engine performance as it can cause damage to the engine, as the engine is being sent into limp mode and can cause further damage to the engine depending on the root of the problem.

What should I do if the reduced engine performance warning persists even after I’ve replaced the sensor or air filter?

If the problem persists, it’s best to take your vehicle to a professional mechanic to check for any other potential causes, such as a malfunctioning throttle body, a clogged exhaust system, or a problem with the fuel system.

Summary

In conclusion, reduced engine performance is a frustrating issue to deal with, but with the right knowledge and tools, it can often be fixed without the help of a mechanic. Remember to always consult your Land Rover manual, and if the problem persists or if you have any doubts, never hesitate to seek the help of a professional mechanic.