Tips for finding an exhaust leak
 

Ok guys I need your help on this one. I'm wondering if you guys have any cool tips or tricks to finding an exhaust leak. I recently installed my FI headers, and there's a loud hiss sound coming from somewhere near the passenger side O2 sensors. I can't pinpoint the location exactly. So far I've tried using a stethoscope and a smoker machine. The smoker uses baby oil to produce a vapor which it then pumps through the muffler into the exhaust system while you block everything else off. We pumped at about 7lbs pressure and found a few tiny leaks, but the sound is still there. I have checked every bolt and everything seems to be tight. I'm gonna try putting some sea foam in the intake manifold and see if I can find something that way. Do you guys have any other suggestions? This sound is driving me nuts, so I really appreciate any help you can give.


Sent from my iPizzle using magic and new-fangled science stuff

Rubber gloves and seal your hands around the area that you suspect is leaking???

Here is a quick vid I made on a how to create a stethascope. I know you said you tried it, but maybe it might help.

https://www.youtube.com/watch?v=G507...s&feature=plcp

You can here a mouse fart with this thing.

That might work normally, but if I could feel it with my hands then I'm sure the smoke we used would have seeped out without a problem.

Thanks for the vid, I'll check it out :tup:


Sent from my iPizzle using magic and new-fangled science stuff

Is that a copper tube or rod?


Sent from my iPizzle using magic and new-fangled science stuff

Are you talking about the hiss on deceleration?

There is that, but it also makes the same noise on acceleration, and the harder I accelerate, the louder it gets.


Sent from my iPizzle using magic and new-fangled science stuff

copper tube from home depot

FWIW - I used a 3 foot piece of garden hose to find where an idler bearing whine was coming from on the wife's Buick a while back. Read about it on some auto repair thread, was hesitant at first but sure as sh*t, it really worked well.

Hold one end next to your ear and put the other end at your suspect locations, if they are the same sound those are probably not leaking, the leaker will be pretty obvious I bet with the hose.

Good Luck - Let us know how it goes.

Awwwww Huck!!!! I hope you get it fixed.

Haha thanks Zgirl, me too! I'm taking it to my buddy's shop tomorrow to put it on the lift and try the sea foam. Thanks fire hawk and rhd for the info. I'll try that out if this sea foam doesn't work :(


Sent from my iPizzle using magic and new-fangled science stuff

let us know how it turns out

Will do!


Sent from my iPizzle using magic and new-fangled science stuff

To find an exhaust leak you could just run seafoam through one of your vaccum lines (brake booster line). Any leaks will spit out white smoke. Do this on my other cars to clean out vaccum lines. Your exhaust will be thick and white for a few minutes.

As far as making a stethescope, I just use a piece of plastic hose to tune the carbs on my 1960 morgan. hold one end to ear and the other to carbs - you can hear them hissing pretty well that way. The owners manual for it actually says to do that.