Exhaust leaking

I have a pestering exhaust leak coming from the connection of my o2 sensor and my exhaust pipe just under my passenger door area. I've tried every sealant at autozone but they all end up cracking and falling off from the heat I'm guessing. Should I look for an o-ring to replace or is there anything else I can try? If I have to I guess I can get a new pipe cut but that could get pricey

 

Threadjack...... but related...... how do you narrow down an exhaust leak? I have replaced my exhaust manifold gaskets like 4 times since i have had my DTLT's and its hard to believe that they are the cause.... how could i tell if it was something else?

sorry, and thank you.

 

I have narrowed the leak to the u2 sensor on the exhaust and I haven't tried an OEM gasket. I never let it bother me enough to go through more than puttying over the leak but it has been mode noticeable since the weather has been nice enough to ride with the windows down and i need to fix it

 

well i only hear it when im driving, not in park at all.... its like a fluttering.... like a card in a bike spoke.... so i cant locate it exactly. and i hate it.

 

I have that also, I only hear it when I'm going between 30 and 50mph and it sounds like yours. I'm almost 100% positive it's coming from the connection of the headers to the motor. The gasket or metal plate there has worn away. You may be able to see some black buildup if this is the case. I don't know an easy fix so I have just left it alone for now

 

yea thats what im thinking.... i just hate having to take the headers off every 6 months to get rid of the leak. i wonder how i can fix it permanently... maybe get the headers machined flat at the flange.

 

Thats probably the best bet. That's how they fixed it on a car show I was watching on spike tv. If there was another way to fix it without taking them off Id love to know