Engine Power Reduced Buick Enclave: Why & What To Do?

Engine power reduced Buick Enclave might strike unannounced at the most unexpected timing – sometimes even mid-driving.

Your job as a responsible, attentive driver is to dig up the root of the problem and treat it as soon as possible before things turn worse.

And my guide aims to lend a helping hand with that through an inclusive suggestion list of the most likely culprits. Keep scrolling.

What Are The Reasons Behind Engine Power Reduced Buick Enclave? 

engine power reduced buick enclave

Buick engine power reduced likely stems from loose connections, faulty sensor issues, bad ECU, clogged catalytic converters, transmission faults, battery problems, worn spark plugs, or low oil levels.

Loose Clamps, Harnesses, or Wires

Each Buick Enclave model arrives with multiple interlocking connectors and wires to power the system.

Thus, just one short electrical wire or loose clamp might trigger a series of back-to-back technical errors.

The best news is that they are recognizable and very easy to fix. (How to do so is a topic I will return to later).

Faulty Oxygen Sensors

As the name implies, O2 sensors measure how much oxygen passes through Buick Enclave’s exhaust system to exit the car and, from there, adjust the fuel-air mixture for the best combustion.

No wonder your car’s power is reduced when the sensors break down.

In worsened cases, both the CEL (check engine light) and the Power Reduced warning light will illuminate together.

Bad Throttle Position Sensors

These sensors are often located inside the throttle bodies (next to butterfly valves), opening up to invite airflow into the Buick Enclave’s engine.

It measures the accelerator pedal position (when stepped on) to inform the computer to what extent the valve should be opened, ensuring the amount of airflow exposure is just right.

Not to mention, throttle position sensors also play a critical role in trans-shifting.

Failure to communicate with other computer systems will hinder the revving regulation, pushing Buick Enclave into limp modes and triggering the Reduced Engine Power light.

Throttle Body Problems

Contrary to popular belief, throttle bodies comprise not just the position sensors.

As briefly mentioned above, we have the butterfly valves, opening and closing at the proper timing to create the right air-fuel mixture.

A rule of thumb is not to let any damage or cracks happen to those valves.

Carbon build-ups are also out of the question; debris clogging the valve’s opening causes your computer to assume its engine does not receive enough air.

As a result, the device will cut off energy and activate the Power Reduced warning.

Bad MAF Sensors (Mass Air Flow Sensors)

Slotted between the intake manifold and the air filter, it measures pressure and air density to guide the computer through fuel-air mixing.

With malfunctioning or, worse, dead MAF sensor, there is no way your Buick Enclave could receive the best combustion.

Faulty ECU (Engine Control Unit)

2010 buick lacrosse engine power reduced

All the ECU sensors communicate with each other to control almost every critical factor of the Enclave’s operation, trying their best to fill in unusual symptoms or oversight inside the engine.

Due to the ECU tackling so many important tasks, its malfunction is considered the most serious on the list; do not be surprised if a basic repair service can cost you thousands of dollars.

Clogged Catalytic Converter

Buick Enclave engine power reduced might also have something to do with the catalytic converters, mounted after the manifold underneath your Buick Enclave.

It is designed to convert CO (carbon monoxide) into CO2 (carbon dioxide) via oxidation and reduction, minimizing emissions during the process.

Not only does its operation failure trigger the CEL and Power Reduced light, but legal issues are also at bay; apparently, driving post-1975 vehicles without catalytic converters is considered unlawful in numerous states.

Battery Problems

Let me clarify: damaged/dead cells or loose grounds will not immediately trigger Reduced Power lights.

Rather, they lead to significantly reduced engine performance and tons of follow-up injuries inside the operational control program – the real causes behind Buick Enclave reduced engine power.

Transmission Fault

All sensors discussed thus far are intertwined with correct transmissions.

So if you find no issues with the sensors, chances are something is wrong with the transmission department; use a scanner to double-check, and you will likely see a transmission error code pop up.

Bad Spark Plugs

The spark plugs work their way into the combustion chamber to ignite your Enclave’s fuel, pushing down the cylinders to move the wheels forward.

It does not take a genius to imagine what will happen if the plugs go bad: Buick reduced engine power, bad acceleration, and, worse, engine misfires, are around the horizon.

Your car will jerk violently during acceleration entries or start-ups.

Low Oil Level in The Engine

Oil works in cars the same way water works in our bodies, lubricating every moving part to guarantee smooth, consistent operation systems.

With little to zero oil, your engine performance will obviously suffer.

Other Reasons

  • Bad ignition switch: Do you fail to start the engine at all? Then try to turn it off to check the switch’s position. If it is still switched to “Run,” the culprit lies elsewhere.
  • Fuel system issues: Something might have happened with the fuel system. Dirty or clogged fuel filters are usually the most common problem, but to avoid missing out, do not forget to give other parts a closer look, too.

How to Fix Engine Power Reduced Buick Enclave 

buick reduced engine power

Here are some tips for returning your Enclave power to normal: 

  • Check loose grounds or wires and reconnect them. For damaged/exposed wiring, buy replacements.
  • Clean or replace the O2 sensors/MAFS/ ECU depending on the problem; use a scanner to identify the engine code
  • Switch to a new throttle sensor or catalytic converter; use quality removal tools if you prefer DIY methods.
  • Clean off the throttle bodies; consider replacing them if your cleaning does not help.
  • Use battery analyzers/testers to check and replace damaged cells
  • Replace transmission fluid and spark plugs
  • Avoid low engine oils; always top them at every 7500 miles.

How Much Does It Cost To Fix Buick Encore Engine Power Reduced? 

Most fixes range between $100 and $500. However, for serious damage or replacements like the catalytic converters or ECUs, expect to spend $2000 or even higher.


Engine power reduced Buick Enclave could be solved easily with DIY or professional mechanic treatments.

However, the complex relationships between its operational engine compartments might rack your total repair costs higher than imagined.

Hence, to keep budgets within control, do not forget to bring the car to regular maintenance services. Also, check for unusual symptoms at least once per month.

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