Well my exhaust leak is so bad that no matter where you are (in or out of the car) you can tell it's coming from the drivers side headers. It's gotten so bad that my car is stalling when I come to a stop in closed loop. Oxygen gets into the pipes and the o2 sensor is reading really high and low values all the time, nothing consistant here. I knew I was having closed loop problems but the exhaust leak wasn't noticable until few days ago when it was almost 70 outside and I had my windows open for the first time all winter! Well, ever since that day it's just been bad and I need to know some cheap ways to locate the leak.
I was thinking of just trying to find it with my hand when the engine is cold but that doesn't work since my fan comes on and blows air around the engine bay with the car on (ignition switched). Is there a way to just rig up a piece of rubber hose and use it as a mechanics stethiscope? I don't want to have to program my eprom to run open loop 24 7 but if that's what'll get me home for spring break without spending $$$ on gas, I'll do it. I'm also thinking about installing a second o2 sensor into the gutted cat but that's a whole nother topic all together.

 

Yes, you can just jam a piece of hose up your ear and probe around with the other end of it.

I'd bet it's the header gaskets, like it always is; probably between the center 2 cylinders where they always fail. Of course, there may be mulitiple leaks, depepnding on how well the gaskets you have fit your head ports and headers. That's a matter of great inconsistency from one combo to another, you may have to experiment a bit to get a gasket that actually seals.

But what difference does any of that make? If it leaks, change it; then no matter where the leak is, hopefully it will be cured. Once you get it apart it will be obvious where it leaks.