Best way to find an exhaust leak? Car smells like

[iboughtatahoe23]

I smell gas in my car for a few minutes, usually only when first starting it up. I know my manifold stud is broken but isn’t leaking, or not to me anyways. I have gotten under the car and listened to where the tick is and can’t seem to find a leak anywhere. I don’t feel hot air or see any black soot what so ever. Maybe I’m not looking in the right spots?

 

[OR VietVet]

Gas smell and exhaust smell are different. May have a fuel leak. If you smell "something" when first start up, I would assume you are smelling the exhaust leak from the broken stud untill the heat takes over and the metal swells slightly and helps restrict the leak. I would still look from front to back for any fuel leaks to be sure.

 

[tom3]

I use a medical type stethescope to find noises and air leaks, really sensitive. A short piece of garden hose with one end at the ear and the other end as the detector works pretty good too.

 

[OR VietVet]

I use a medical type stethescope to find noises and air leaks, really sensitive. A short piece of garden hose with one end at the ear and the other end as the detector works pretty good too.

One of the most important tools in my tool collection. In a pinch, I have used a long screwdriver to put the tip on the suspect noise source and the end of handle at my ear. Recently, I used my mechanic's stethoscope with a rubber cup end on a tube that attached to the hoses going up to the ears and could hear when a rear parking sensor was not working. I could hear that "geiger counter" pulsing sound.

 

[iboughtatahoe23]

Gas smell and exhaust smell are different. May have a fuel leak. If you smell "something" when first start up, I would assume you are smelling the exhaust leak from the broken stud untill the heat takes over and the metal swells slightly and helps restrict the leak. I would still look from front to back for any fuel leaks to be sure.

Most common failure spot for leaks?

 

[OR VietVet]

Most common failure spot for leaks?

Exhaust-manifold broken bolts. Fuel-seal at top of fuel tank where the pump drops in or a line.

 

[j91z28d1]

I'd guess it's the manifold.

something like this, but take the end off so it's a open hose and drag it around where the manifold meets the head, especially the underside. I have the clamp installed and sware it still leaks a bit when cold. probably carbon build up on the gaskets from the previous owner driving it like that for years.

have someone else start the truck while you listen, you'll hear the puff puff of a leak easily with the open hose.

 

[OR VietVet]

This is the one I have and I really like that cup for close up noises: https://www.amazon.com/Lisle-52750-...6620107&sprefix=mechanics+stet,aps,175&sr=8-5

 

[Charlie207]

I saw a cool hack where you cut the bottom off of a gallon wiper fluid jug, and jam the handle of a long screwdriver into the mouth of the bottle. You essentially make a megaphone, and it's pretty effective.

 

[iboughtatahoe23]

Exhaust-manifold broken bolts. Fuel-seal at top of fuel tank where the pump drops in or a line.

So that count as a leak and can cause a tick?