05 Corolla Exhaust Leak
- Thread starter The Critic
- Start date
This type of joint requires a smooth surface for the donut to seal against. Sealers of any kind are out.
Well, muffler guy’s recommendation worked. At least for now.
Fixing this exhaust leak also resolved my fuel trim issue since Toyota uses the rear o2 for fuel control. Trims went from +14 to +8, almost immediately.
He is selling me the spare flange for when this bandaid repair fails, which I’m sure it will.
I think all that damage was it leaking and the hot exhaust gases were like a blowtorch all the way around. Eroding the metal. Or the connection was so loose it rattled together and apart back and forth eroding it. Either way it took a while.
I cant see any sealant working long term on a flange type connection.
I cant see any sealant working long term on a flange type connection.
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The gasket will degrade into, basically, valve packing. On steam valves we used to use asbestos yarn but now use graphite, remarkably similar (IMO) to exhaust donut gasket material. The orange RTV will take the shape of the pits. The graphite won't really feel obligated to stick to it, and if it did, the inside portion will still slide against the "ball" sticking out of the manifold. I suspect this rigging job will last longer than most people expect.
I just finished smoke-testing the exhaust for 10 minutes. Surprisingly, it passes with flying colors: there is zero smoke coming out of that connection.
Sure it works, exhaust cement will work too till it fails. Any exhaust leak before either of the O2 sensors is going to cause fuel trim issues on any car.
I had one that had +20 fuel trims intermittently, it was a crack on the cat hanger mounting after the front AFM but before the rear O2, no rust just a stress crack that would open when the car hit a pot hole or speed bump. I welded the crack, ground it down then made a nice reinforcement to weld over it which lasted for years, it may still be in service.
I had one that had +20 fuel trims intermittently, it was a crack on the cat hanger mounting after the front AFM but before the rear O2, no rust just a stress crack that would open when the car hit a pot hole or speed bump. I welded the crack, ground it down then made a nice reinforcement to weld over it which lasted for years, it may still be in service.
I put 400 miles on the car under a variety of conditions. The repair appears to be holding. For now, I have released the car to my sister and will report back if the issue returns. If it does, I will get the replacement flange welded.
It has been more than 2K since this mickey-mouse repair was performed. Surprisingly, the repair is still holding up.
Hey @The Critic I now own an 2008 Corolla and working on a 2007 Corolla, they have this exact same issue
Your link for the exhaust donut flange doesn’t seem to work, were you able to find one to be welded or is your temporary fix still holding?
I would like to buy just the exhaust donut flange and get them welded if possible
Any overall suggestions? @Trav and @The Critic
Something like this would have been my first attempt to repair it as well. Either that or infill with some (epoxy?) or something that's heat resistant, then smooth out (to restore to original dimensions) and use a gasket with some sort of sealant.
Local muffler shop gave me one from an old catalytic converter that was still in good shape. It is on my to-do list to get it welded.
The RTV fix actually held for over a year until I had to raise/lower the engine to replace the lower control arms; that was when it unsealed itself.
the whole Cat or just the exhaust flange portion?
I wish I could find an overall solution to this as I currently own the following:
2005 Toyota Corolla S Auto w/244k miles - doesn't have this issue but eventually, it does get 32-33 mpg even @ higher speeds
2008 Toyota Corolla S Auto w/100k miles - has this issue and fuel trims must be off as I get 28 mpg avg on the highway which is low for a 1zzfe engine car
I will be maintaining the following as well:
2007 Toyota Corolla S Auto w/146k miles - also has the issue.
Just the flange.
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