172 cat to centre section join blowing

[172_Tom]

My exhaust is blowing from the cat to middle section join. It has a thin metal gasket on it and has been sealed up with high temp silicone sealant. Looked under the car and there was a bit of silicone hanging down from the join.

Is the thin metal gasket between the cat and middle section all there is supposed to be? Any tips for getting it sealed up properly?!

 

[Gaverick]

I had big issues trying to get mine to seal. The flange on the cat had warped. I ended up cutting the flange off the cat and making a sleeve join with the centre section.

 

[172_Tom]

Still got a leak from the cat to mid section even after fitting a new Renault gasket :rage:Will give the garage another shot at fixing it before I look at other options.

Should I use high temp silicone to seal it? If I use that should I do it without the gasket?
If it ends up needing to be sleeved does the post cat lambda sensor not get in the way of sleeving it? Can't remember how close it is when I last looked under the car. If anyone could recommend a decent exhaust place in West Suffolk/South Cambs/North Essex/North Herts that would also be helpful.