I blew off the clamp from my throttle body. Ever since that happened, I kept getting codes for my cat below threshold efficiency (p0420). Is it possible to kill a cat just from blowing off a pipe?
car has a full turbo back exhaust.

 

No.

What exhaust are you running?

 

no cat has nothing 2 do w/ it. that code just means ur cat is bad or the rear o2 is going. now ur pipe blowing simply means when ur hitting boost ur crappy stock clamps arent holding. try getting tbolt clamps.

 

Definitely two seperate issues.

 

Do you have a CAT in your full turbo back exhaust or is there a test pipe?

When you blow an IC pipe off, you typically run very rich for a second and usually there is a pretty big back fire and fire ball to match. I suppose it is possible that the backfire damged you CAT or your 02 sensor. But I dont think that is really that likley.

 

I just had the same issue. My IC pipe blew off at the track on Sunday. I got towed in, re-tightened the POS clamp in the pits, and kept going. Next day I ended up with a P0420. I cleared it and it hasn't returned yet.

 

I blew the same i/c pipe and get a CEL. The cel was something like 'throttle plate etc'... not sure though.