Gutting the catalytic converter

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[url=https://imoc.co.uk/app.php/kb/viewarticle?a=11&sid=b5070f8554edf5573d280da6fccd4bdc]Knowledge Base - Gutting the catalytic converter[/url]

\\Gutting the cat\
by Leon\


I did this the other week, and have to say it was a complete ball-ache of a job that took me about 10 hours altogether! My tubby is a rev2 but I\'d imagine the process will be almost identical for the rev3. I know the turbo elbow is slightly different though...

It sounds easy on paper- there are about 10 bolts holding 2 covers under the car, remove these along with covers. Next, unbolt the forward exhaust pipe from the rear section (2 bolts) and un-bolt the forward section of exhaust from the bottom of the cat pipe (2 nuts, 1 bolt). For me at least, all of this was easy.

You\'re now left with 6 bolts and 2 nuts holding the cat pipe in place. There are 2 on the right hand cat bracket, 1 on the left hand cat bracket, 3 bolts holding the cat pipe to the turbo elbow, and 2 nuts also holding the cat pipe to the turbo elbow.

There\'s also the cat temp sensor screwed into the bottom of the cat pipe. You\'ll either have to remove this or cut the wire leading to it in order to fully remove the pipe.

Whichever order you tackle these nuts/bolts is up to you. I managed to remove both bolts from the left hand cat bracket and 2 bolts from the cat pipe-to-turbo elbow flange in one piece. The other nuts/bolts on the cat pipe-to-turbo elbow flange snapped off, and the single bolt on the right hand cat stay bracket rounded off straight away. I then had to spend over 3 hours with a hacksaw, first removing the head, and then cutting between the cat pipe and the bracket itself to release the last bit of bolt holding it in place.

My cat temp sensor was seized beyond belief so I cut the wires leading to it. At this point the cat pipe still didn\'t drop down, and I had to bend the left hand bracket a bit further to the left in order to finally release it.

Once off the car, the gutting part took about 3 seconds- my cat internals were loose and just fell out when the pipe was turned upside down. I removed the heat shields, drilled out all snapped bolts/studs, then re-assembled everything with new bolts, studs, gaskets and PLENTY of anti-seize compound.

I\'d been told that you got a dash warning light if the cat temp sensor was disconnected from the ECU, and was planning to re-connect the wires I\'d cut but I never got a warning light anyway so I just left them cut.

I\'d suggest you buy new bolts, nuts and gaskets prior to the job so that you don\'t have to worry about snapped bolts and leaking old gaskets.