I have been fixing up my sidekick I just bought and I just installed a new cat (didn't have one), resonator, and muffler.  Spent the time to weld it together and put in hangers to find a leak between the manifold and the Y pipe that goes to the cat.  The previous owner had drilled out and put in helicoils and some bolts were loose.  I pulled it apart and there were two gaskets that were inbetween the flanges.  One was a paper style with metal rings and one was a metal gasket.  I used copper RTV between all surfaces and mounted everything together with new hardened bolts and gave the rtv a day to dry.  Well it was nice and quiet for a days worth of driving but now the leak is back. Its between the two rear bolts on the flange. I know things are cranked down tight so I assume something isn't flush and it blew the RTV out.  Is that all that is supposed to be between these two parts is the two flat gaskets?  Before I started this project I went to autozone and asked if they had a replacement gasket but they brought out a circular metal flange gasket.  Any ideas?

It really sucks to have spent the time and then be stuck on this last part. 

Lucky you!

I just posted the engine section of the '96 Tracker FSM at Ack's FAQ.  While it may not be exactly the same as your Sidekick (it deals with a 16-valve engine), you should find the information useful.

http://www.acksfaq.com/trackerfsm.php

Look for Section 6A1.

By the way, check your exhaust manifold (I assume that it is OEM) for cracks or warpage. This might be contributing to your problems

It sound like you have a warped flange and the previous owner has already tried to fix it. There should only be one gasket between the two flanges.

Thanks for the link.  I may try to pull it apart and remove the metal gasket and see what happens.  I have a feeling that it may be warped.  So my next question is if I pull the manifold off and remove my downtube before the cat and try to weld the downtube to the manifold will that work?  I guess the question is if the manifold is made of metal that will take a weld?  Or do you think that the vibration will just brake it loose after a while?  I am trying to low budget it as I already have more invested in aftermarket parts than the $1000 I paid for the 1992 vehicle.  :^)  I have seen new manifolds on ebay for $70 and downtubes for $30 so if I had to I could go that route.  Is it safe to say that rtv does nothing in this situation as even their copper series rated at 700F doesn't seem to handle the heat? 

RTV on any part of an exhaust system is an exercise in futility. It is possible to weld a cast iron manifold, needs to be done by a pro, with a high nickle content wire. By the time you get done repairing everything, you could probably throw a header on in it's place for about the same cost and be done with it.

I delt with this problem twice, the first time I spent $130 having the surfaces machined flat and new threads for the O2 sensor, after it was done there was still a crack forming on the inside webbing, the second time I bought a Doug Thoreghly Header. Buy a header, save yourself the headaches. and more power  besides I was tired of carrying a wrench around to keep tightening it, and bloody civics kept trying to race me at every stop light.

as a note, a tracer with open headers sounds like a P-51 around town, well more like a Piper Cub.

I looked real hard tonight deciding if I was going to rig it or not.  THen found a crack on the original manifold that is on the front cylinder tube.  No exhaust was coming out of it but I figure if I am going to go through the hassle of pulling the manifold I am not going to put a cracked one back on.  So I ordered a header through RRO.  My TSL 31/10.5/15's and rims are scheduled to arrive tomorow so maybe the header will make the change from 235's less noticable power wise.  I guess there is a point where you can't explain/reason where the money went anymore.     I am there.