An exhaust leak can lead to many problems. If you’re lucky, it won’t cause you many issues, apart from some strange noises.
But in most cases, it’s the cause of serious performance problems in a vehicle. It can affect fuel consumption and trigger the “check engine light.”
The worst scenario in the case of a major leak could be that the car’s cabin fills with carbon monoxide, a toxic gas.
That’s why we need to find the causes and know how to detect an exhaust leak as quickly as possible to ensure your vehicle’s safety. Let’s take a look at the details below.
Signs that the car’s exhaust pipe is malfunctioning
Fuel-powered vehicles generate emissions. Typically, these exhaust gases are expelled through the vehicle’s exhaust system.
So, let’s examine the signs below indicating how leaks are emitted from the car’s exhaust pipes. This will help you know how to find an exhaust leak and methods for exhaust leak repair.
1. The bad smell emitted by the car’s exhaust pipe
When driving a car, if you notice that the exhaust pipe is emitting an unpleasant odor, it means the exhaust pipe has been misused, with poorly treated exhaust gases or simply a leaking exhaust causing a bad smell.
So, this is the time when you need to replace your car’s exhaust pipe.
2. The check engine light comes on
The engine light will come on if the exhaust does not meet standards.
Car owners undergoing inspection, if detected, must quickly receive instructions to repair and fix it in time to ensure safety while driving as well as to ensure emissions meet environmental standards.
3. The automobile’s exhaust pipe makes noises
When the vehicle is running, if the exhaust pipe detects noise, it is also an important sign indicating that you need to check the exhaust.
Typically, the exhaust pipe makes more noise when it’s leaking. Immediately take the vehicle to a repair shop to avoid rapid degradation if the problem is detected.
How to detect an exhaust leak
The first step to repairing such a leak is to find it. If you think there is a problem with your exhaust system, there are several ways to find it.
Small exhaust leaks often show up as some soot around the outside of the pipe. So, simply look for this black soot when inspecting the entire exhaust system.
Inspect particularly the flexible joints (usually emissions are hidden under the mesh, so you need to pinpoint to find where an exhaust leak is coming from)
Preparation before the trick to find an exhaust leak
So, before moving on to the part: How to find an exhaust leak? We need to prepare a few things to meet all the necessary conditions.
The first thing is to find someone to do this job with you.
Secondly, lift your vehicle to get a good view of the exhaust system (use an axle lift).
And you need to go under the car to get an overview of the exhaust system, so this way, you can inspect the whole thing.
Specific steps to fix your car’s emissions leaks
| Step | Description |
| 1 | Start the vehicle |
| 2 | Listen to your car’s noise to inspect the sound of the exhaust system |
| 3 | Take a look in your car’s muffler and stuff a new cloth into the exhaust, this will make leaks more apparent (tell your partner to look around your car while you do this) |
| 4 | You will hear the leak noise clearer and better, and there should be a small amount of leakage at the outlet hole at the back of the muffler if there are exhaust leaks in your car. |
| 5 | Take a closer look at the exhaust system by removing the cover. |
| 6 | Observe the manifold inside to check if the leaks are coming from the downpipe. This will help you clarify the position from which the leaks are coming out. |
How to repair an exhaust leak
Methods vary slightly depending on the size of the holes. You will use an exhaust patch for small perforations while larger ones will require an aluminum patch.
Repairing a leak – more or less significant
Use a steel brush to scrub the area around the leak. Clean thoroughly to remove rust, mud, or dirt.
Smooth the clean surface with fine-grit sandpaper. This will remove tiny dirt particles that survived the steel brush.
Rinse the cleaned area with acetone (or nail polish remover if you don’t have this chemical). This will help the tape form a stronger bond with the metal surface.
If it’s a small exhaust leak, use exhaust tape or epoxy.
Follow the application instructions provided with the tape, as some adhere well to a hot surface while others require it to be wet. Use at least two layers of tape for a stronger, tighter wrap.
If the hole is larger but still smaller than three inches, you can repair it with aluminum patches.
Anything larger than that will require replacing the entire part. You should always apply the epoxy before putting the aluminum patch over the leak area. Use hose clamps to hold the patch firmly around the exhaust pipe.
Never forget to wear glasses and gloves. Otherwise, dirt and rust particles can get into your eyes and acetone can irritate your skin. Also, take the car to a maintenance workshop if the leak is larger (more than 3 inches / 7.5 cm).
All the information above has shown a clear way to answer the question: How to find an exhaust leak and has also published some methods for repairing an exhaust leak when using the car.