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Can an Exhaust Leak Cause Loss of Power? (Explained)

Updated: Jan 9

An exhaust leak can allow extra air into the exhaust system or will cause exhaust gas to exit before the oxygen sensors. The oxygen sensor provides critical data to the ECU, allowing the engine to run smoothly.

If you have an exhaust leak you may have noticed reduced acceleration, so can an exhaust leak cause loss of power? Yes, if the oxygen sensor sends incorrect data to the ECU, it can cause loss of power and reduced performance.


Table of Contents:

example of an exhaust leak
An example of a broken exhaust pipe causing an exhaust leak.

What Is an Exhaust Leak?

The exhaust system of a vehicle is responsible for directing the exhaust gases away from the engine and out of the vehicle. It consists of various pipes, mufflers, and catalytic converters that work together to reduce noise and harmful emissions.

An exhaust leak occurs when there is a hole or break in one of these components, allowing exhaust gases to escape.

Symptoms of a Leaking Exhaust System

There are several indications of an exhaust leak, including the following.

  • A loud or unusual noise coming from the exhaust pipe

  • A decrease in fuel efficiency

  • An increase in engine noise

  • An unusual smell coming from the exhaust pipe

  • Visible damage to the exhaust system components

If you notice any of these symptoms, it is important to have your exhaust system checked by a mechanic as soon as possible. If you have an exhaust leak you should have it fixed as soon as you can (see how to fix an exhaust leak here).

Can an Exhaust Leak Cause Loss of Power?

An exhaust leak can cause a loss of power in a vehicle for several reasons. The exhaust system contains sensors called oxygen sensors, these provide the ECU with data on the air/fuel mixture.

If the oxygen sensors send incorrect data to the ECU, which often happens when the exhaust is leaking, it can alter the air/fuel ratio the engine is using, this can affect the performance of the engine and affect how it runs.

An exhaust leak can cause the engine to run lean, which means there is not enough fuel being supplied to the engine to support optimal combustion, this can also lead to a loss of power.

Sometimes the engine may misfire due to an exhaust leak, this could result in engine knocking, causing the ECU to limit power even further.

Can an Exhaust Leak Cause Poor Acceleration?

If the engine is producing less power, the acceleration of the vehicle will also be reduced, it can do this in three ways.

  • Sub-optimal air/fuel ratio: The ECU may limit power due to running a sub-optimal air/fuel ratio.

  • Engine knocking and misfiring: The ECU may reduce power to prevent damage due to misfiring and knocking.

  • Limp mode: In some cases, the ECU may even put the vehicle into limp mode, causing poor acceleration.

Is It Dangerous to Drive With a Leaking Exhaust?

It is not recommended to drive with a leaking exhaust system. In addition to causing a loss of power and poor acceleration, an exhaust leak can also be dangerous.

Exhaust gases contain harmful chemicals, such as carbon monoxide, which can be lethal if inhaled. A leaking exhaust can allow these gases to enter the cabin of the vehicle, putting the occupants at risk.