Find an exhaust leak

Use a shop vac and a spray bottle to find an exhaust leak.

The easiest way to find an exhaust leak is to pressurize the exhaust system using an ordinary shop vacuum and a spray bottle filled with water and dishwashing detergent.

What You’ll Need

Shop vacuum or wet/dry vac with a hose
Duct tape or aluminum tape.
Soapy water solution in a spray bottle
Flashlight

Preparing the Vehicle

Before starting, ensure the engine is cool if it has been running recently. You’ll also want to give the entire exhaust system a thorough visual inspection, looking for any obvious holes, cracks, or loose connections or clamps.

Perform a visual check first

Many exhaust leaks give visual clues and the most common is a dark patch of soot at the connection.

Using the Shop Vac to pressurize the exhaust

With the vehicle safely raised, connect the vacuum hose securely to the tail pipe using duct tape or aluminum tape. Set up your shop vac so the hose is in the blow position.

Spray all exhaust connections with soapy water

With the shop vac running and pressurizing the system, start at the front of the exhaust system, spraying soapy water on every connection. Look for bubbles. The most likely culprits are the flange connectors, and oxygen sensors.

©, 2021 Rick Muscoplat