How To Find Exhaust Leak With Soapy Water: An Ultimate Guide

It’s important to find exhaust leak with soapy water and fix it to prevent further problems with your automotive engine.

This exhaust leak in your vehicle is a nuisance since it increases the abnormal noise produced by the engine and makes exhaust gasses penetrate the cabin.

Therefore, this issue can cause damage to your vehicle and endanger you while driving.

This is why it is significant to learn more about identifying an exhaust leak using soapy water to repair it without hassle.

Keep reading this article for useful information about the exhaust leak and a complete guide on finding and fixing it.

What Is an Exhaust System?

find exhaust leak with soapy water
An Exhaust System

An automobile exhaust system is an essential interconnected assembly of sensors, fittings, pipes, and mechanical units installed to process and treat the exhaust gasses resulting from the engine’s combustion process.

This vital system includes three main functions below: 

Keep exhaust fumes away from the passengers and driver and silence the sound produced by the engine’s internal combustion process.

It also makes the exhaust cleaner from toxic emissions harmful to the environment and humans.

How To Find Exhaust Leak With Soapy Water

How do you find an exhaust leak? You need to use a spray bottle to identify an exhaust leak with soapy water by pumping air through the exhaust pipe.

Spray soapy water is easy to find the leaks on the exhaust manifold while the air pressurizes the automotive exhaust system.

If you see bubbles coming from where you sprayed the soapy water, it’s a common symptom indicating that the leaky exhaust appears.

Exhaust fumes can escape from multiple locations, so don’t stop spraying it with soapy water if you see bubbles in one area.

Below is an ultimate guide to finding the leaks in this automobile part.

Do Visual Inspection

As soon as you find exhaust leak in your car, the first necessary thing to do is determine whether you have worked on the exhaust system before or if you have somehow removed the exhaust system while checking other automotive parts.

In this case, you should visually inspect the area you worked on. It’s important to check the gaskets, connections, and exhaust pipe for cracks.

Yet, you should note that the exhaust manifold can be hotter than other automotive components. Thus, don’t put your fingers on the exhaust vent if it is hot (after a drive) to avoid burning them.

Spray the Soapy Water

After detecting the exhaust system leak, spray the suspect area with soapy water. You can implement this task by filling a spray bottle with water and soap.

The exact ratio doesn’t matter as long as it foams once sprayed onto the surface. This simple method is how to find exhaust leak on car easily.

All you must prepare here is soapy water with gloves, duct tape, or anything to direct the air through the exhaust system.

Connect Leaf Blower Or Air Compressor To The Exhaust Tailpipe

Connect the hose to the blower outlet instead of the vacuum inlet. Then, turn it on to start working after linking the vacuum cleaner to the air vent.

Crawl under the vehicle and spray soapy water on the suspect area.

You can begin with pipe connections that are clamped, bolted, and welded. Then spray it all over the exhaust system to inspect and look for other leaks.

Remember that leaks become visible when air bubbles form at the source.

Also, a large leak just blows away the water and soap. Besides water and soap, you must put your hands on different areas of the exhaust system to feel the airflow.

This will help you know how to diagnose an exhaust leak without difficulty.

Turn On Leaf Blower or Air Compressor

Insert plugs the blower into the tailpipe and ensure it is securely fastened with tape for better attachment. Enable your air compressor or leaf blower, depending on what you utilize.

Prepare a spray bottle with the proper soap and water to spray on the suspect area. This is a simple way to do it if you don’t know how to find exhaust leak in your vehicle.

Pinhole Leak

The last step of  how to detect an exhaust leak in your car is to pinhole leaks with something convenient such as colored pencils. Also, give it an easy replacement or repair.

If you can’t fix or the leak is way too serious, bring your vehicle to an auto repair shop for help.

What Are the Symptoms of An Exhaust Leak?

how do you find an exhaust leak
Signs of An Exhaust Leak

Strange Smell

A strange smell will appear in your engine system if there is a leak in the exhaust pipe,  especially close to the catalytic converter. If this smell persists, it’s toxic carbon monoxide from the tailpipe.

It is a serious cause of fatal diseases and other health risks; crack open your car’s windows if you find this abnormal smell while driving, and take it to a mechanic.

Abnormal Vibrations & Raspy Sound

Cracks, bad seals, or air leaks through holes are the main culprits of abnormal mental vibrations.

If you detect the gritty, thumping, or ticking noise in the automotive engine bay or under the car while accelerating, your vehicle includes an exhaust leak.

Regardless of the leakage, vibration and noise may occur as smoke escapes. Yet, larger leaks may create annoying noises and vibrations affecting the steering wheel.

Also, you can note that the noise from the exhaust leak will get louder if you accelerate.

Poor Gas Mileage & Low Fuel Efficiency

You may avoid or ignore the oxygen sensor, which is necessary for optimal combustion, depending on the leak’s place.

If the oxygen sensor fails to give an accurate reading, your car’s ECU may be telling the vehicle to consume more fuel, negatively affecting fuel economy.

Another case when your vehicle eats up extra fuel is there is an exhaust leak near the exhaust manifold that can reduce the vehicle’s efficiency by about 3-4 mpg.

This is because the automotive exhaust system bypasses the O2 sensor detecting oxygen exiting and entering the exhaust system.

Check your exhaust system as soon as you note a drop in fuel efficiency to avoid wasting money on topping up gas.

Loud Noise

If you start the engine and hear tickling, wheezing, or other unpleasant sounds coming from the engine compartment, it means a leak in the exhaust manifold gasket.

The gasket is between the cylinder head and the exhaust manifold. This loud sound may also originate from the automotive exhaust flange connection.

How Can You Fix After Finding An Exhaust Leak?

finding an exhaust leak
How To Fix After Finding An Exhaust Leak

After finding exhaust leak, using sealant to fix it with putties and tapes, despite being the most common method, is a temporary fix.

Thus, you need to get tightening if your exhaust leak appears because of losing connections.

Besides, tightening the loose joints and bolts is also enough to handle the exhaust leak.

In another case, an exhaust leak is due to a hole; you may weld this broken place as a sealant for a specific position.

But this way needs support from a professional mechanic owing to being a more extensive fix.

In addition, you can repair your exhaust leak by yourself at home with the right products and tools from the auto shops.

Finding the right items at online stores to repair exhaust system leaks is simple and affordable.

However, it’s best to take your vehicle to the expert mechanics for a complete inspection and a thorough fix.


Is It Safe to Drive With The Exhaust Leak?

No. Carbon monoxide in the exhaust gas is dangerous to human health, so driving with an exhaust manifold will harm your health.

A leaky exhaust can lower fuel efficiency and increase the engine’s workload, leading to higher fuel consumption. You will soon notice these if you insist on driving with a leaky exhaust manifold.

How Much Will It Cost to Repair an Exhaust Leak?

The repair cost of an exhaust leak can depend on factors, such as the automotive model, year, car manufacturer, number of cylinders in the tailpipe, and where you get the repair done.

Repairing an automotive exhaust leak takes about 1-2 hours. Most dealers charge between $70 and $100 per hour. Therefore, you will have to pay about $140 to $200 for exhaust leak fixing service fees.


We’ve covered an ultimate guide on how to find exhaust leak with soapy water.

To identify a leak or more leaky areas in the exhaust pipe, you must prepare a bottle of soapy water to spray into that position.

Besides, use an air compressor, a leaf blower, with tapes and gloves or anything to detect the leak in the system.

After finding the exhaust leak in your vehicle, you can fix it in multiple ways, such as using sealant and tightening the loose connections, bolts, or joints.

Yet, you must give your vehicle regular maintenance and thorough inspection to detect unwanted leaks in the exhaust system.

This is useful to help you solve your automobile’s serious problems better and more effectively.

If your car gets an exhaust leak, it’s best to take it to a professional mechanic for a quick and complete repair.

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