How to find exhaust leak?

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May 25, 2005
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So I've been trying to track down the exhaust smell coming into the cabin of my 2005 Dodge Neon when not moving. Yesterday after a long drive i let it idle popped the hood and could smell exhaust at the back of the engine, not sure if it's a leak in the exhaust manifold or the pipe that connects to it. The exhaust is not smoking so, how or what methods can I use to find the leak? I'm starting to get this tracked down but have never had this happen on any of my previous vehicles. All help appreciated.
 
Filling the exhaust system with smoke will assist locating the leak(s). You can purchase an affordable automotive smoke machine/leak detector from Amazon/eBay (Auto Tool brand comes to mind). Alternatively- go on YouTube and lookup DIY automotive smoke machine.
 
Cheapest way have a friend hold a couple rags folded up over the tail pipe while you feel around the engine exhaust.
 
Shop-Vac and a spray bottle of dishwashing soap and water...

Reverse the Shop Vac to blow by switching the hose to the other side.

Shove up tailpipe.

Spray water / soap mixture, look for bubbles...
 
Sometimes an incense stick can help, you can watch the smoke move or the tip glow - depending on location.
 
Are you positive it's not an oil leak burning on hot engine parts or blowby smell from the engine?

Sometimes oil leaking into the sparkplug wells will give off oil smell once hot.
 
Take length of garden hose and pass one end over the exhaust system with other end against your ear, while engine is running, you will be able to hear and pin point leak.
 
^^^^^^^^^^^^^ This.
I don't use a garden hose, just a short section of vinyl hose laying around in the shop. (Hose type isn't that important.)
You can easily hear any exhaust leak.
 
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In carburetor engines I would dump a little bit of transmission fluid down carburetor. On newer ones Seafoam in vacuum line and let sit. Start it up and check where smoke is coming from. Doesn't take much.
 
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