top of page

Wastegate Rattle (Causes & Fixes)

Updated: Jan 8

If you own a turbocharged car, you may have heard of something called a wastegate rattle. This can be a frustrating and potentially serious issue that can affect the performance and efficiency of your vehicle.


In this article, we will delve into what a wastegate is, what wastegate rattle is, and how you can fix it.

 

Table of Contents:

 

What Is a Wastegate?

A wastegate is a valve that is used to control the amount of boost pressure that is produced by a turbocharger. It is designed to open and release excess exhaust gases when the turbocharger is producing more boost pressure than is needed.


This helps to prevent the turbocharger from over-speeding and damaging the engine.


The wastegate is typically controlled by a valve that is actuated by a wastegate spring. When the spring is relaxed, the valve is closed, and when the spring is under tension, the valve is open.


The spring is usually held in place by a rod that is connected to the wastegate actuator. The actuator is a small hydraulic or pneumatic device that is used to control the wastegate valve.


an internal wastegate on a turbocharger

What Is Wastegate Rattle?

Wastegate rattle is a condition that occurs when the wastegate valve and actuator start to make a knocking or rattling noise. This can happen when the wastegate valve is not operating correctly, or when the actuator is not functioning properly.


Wastegate rattle can occur at any time, but it is most commonly heard when the engine is idling or when the car is accelerating. The noise may be more pronounced when the car is under load, such as when driving up a hill or towing a trailer.


How Serious Is Wastegate Rattle?

Wastegate rattle is generally not a serious issue, but it can be frustrating for the driver and can potentially lead to other problems if left unchecked.


If the wastegate valve is not operating correctly, it can cause the turbocharger to produce too much boost pressure, which can lead to engine damage.


Additionally, wastegate rattle can be an indication that the wastegate actuator is not functioning properly.


If the actuator is not working correctly, it can affect the performance of the wastegate valve and may cause the turbocharger to produce too much or too little boost pressure. This can lead to poor engine performance and fuel efficiency.


What Happens if You Don’t Fix Wastegate Rattle?

If you don’t fix wastegate rattle, it is likely that the issue will continue to get worse over time. The noise may become louder and more frequent, and it could potentially lead to other problems with the wastegate valve or actuator.


If left unchecked, the wastegate valve may become stuck in the open or closed position, which can affect the performance of the turbocharger and potentially cause engine damage.


What Causes Wastegate Rattle?

There are several potential causes of rattling wastegate. Some common causes include the following.


  • Worn or damaged wastegate valve or actuator: If the wastegate valve or actuator is worn or damaged, it can cause the parts to become loose and make a knocking or rattling noise.

  • Incorrectly adjusted wastegate actuator: If the wastegate actuator is not adjusted correctly, it can cause the wastegate valve to open and close at the wrong times, which can lead to wastegate rattle.

  • Loose or worn wastegate rod: If the wastegate rod that connects the actuator to the wastegate valve is loose or worn, it can cause the parts to move around and create a knocking or rattling noise.

  • Excessive boost pressure: If the turbocharger is producing too much boost pressure, it can cause the wastegate valve to open and close excessively, which can lead to wastegate rattle.


How Do You Fix Wastegate Rattle?

If you are experiencing waste gate rattle, there are a few steps you can take to try to fix the issue.


  1. Check the wastegate valve and actuator for wear or damage: If the wastegate valve or actuator is damaged or worn, it will need to be replaced.

  2. Adjust the wastegate actuator: If the wastegate actuator is not adjusted correctly, it can cause the wastegate valve to open and close at the wrong times, leading to wastegate rattle. You can try adjusting the actuator to see if it fixes the issue.

  3. Tighten the wastegate rod: If the wastegate rod is loose or worn, it can cause the wastegate valve and actuator to move around and create a knocking or rattling noise. Tightening the rod may help to fix the issue.

  4. Reduce boost pressure: If the turbocharger is producing too much boost pressure, it can cause the wastegate valve to open and close excessively, leading to wastegate rattle. You can try reducing the boost pressure to see if it helps fix the issue.


In addition to the steps listed above, there are a few other things you can try to fix wastegate rattle.


  • Clean the wastegate valve and actuator: If the wastegate valve and actuator are dirty or covered in debris, it can cause them to function improperly and lead to wastegate rattle. Cleaning the parts may help to fix the issue.

  • Replace the wastegate spring: If the wastegate spring is worn or damaged, it can cause the wastegate valve to open and close at the wrong times, leading to wastegate rattle. Replacing the spring may help to fix the issue.

  • Replace the wastegate rod: If the wastegate rod is worn or damaged, it can cause the wastegate valve and actuator to move around and create a knocking or rattling noise. Replacing the rod may help to fix the issue.


It is important to note that wastegate rattle can be caused by a variety of factors, and it is not always easy to pinpoint the exact cause of the issue. In some cases, multiple issues may be contributing to the wastegate rattle.


It is always a good idea to get a professional diagnosis to determine the cause of the issue and the best course of action for repair.

If these fixes don't work you may need to repair or replace the wastegate or related components.


Wastegate Rattle Fix Cost

The cost to fix wastegate rattle will depend on the cause of the issue and the parts that need to be replaced. If the wastegate valve or actuator is worn or damaged, it will need to be replaced, which can be a costly repair.