[paulmanchester]

Have a bypass pipe on back order, so took the cat off in anticipation.
One end looks to have a metal grid, but the other end looks like rubble of a building site. Do cats normally look like this. I would imagine this is not good - what problems could this have caused (hoping for a boost related reply. At high revs would this cause substantial boost tail off?)

 

[mikehunter]

Sounds like its f***ed. Been through any fords (the watery type) recently? Sudden temperature changes can crack up the ceramic or perhaps it was just vibration.

Effect on boost would depend on how much the flow of exhaust gasses has changed from a normal
cat.

You can save the money on the cat bypass now - just shake the rubble out and put the cat back!

 

[wedgepilot]

I'm surprised you didn't hear anything! When the cat went on my wife's car (not a Saab admittedly), it made a hell of a racket. Performance dropped off badly as well due the blockage.

Alan