My high milage 260e has been due for a catalytic converter replacement for some time. It has the California model, but since I moved to Washington in a county where emmissions tests are not required, a local mechanic told me that it would be cheaper to just remove the cat myself and bore it out. I've never done any work on emmissions systems before, and would like to know how easy this is. The rear part of the cat is connected with bolts, and the front is permanently connnected to the exhaust headers. </P>


Do I have to disconnect the exhaust headers from the engine and the bolts on the cat in order to bore it out, or can I just remove the rear bolts? Also, could I just use a rifle brush to bore it out, or is this process more complicated than I think? (New cats are over $500 wholesale.)</P>

 

One more thing: would boring out the cat negatively affect the engine? I was told that Mercedes need a certaint ammount of backpressure to function properly, and that boring out the cat would mess the computer up. Is there any truth in this, because the accelleration has really declined as the milage has increased, and think that boring out the cat would be an improvement.