Boughg rx8 running rough did tune up it was only running off 2 coils. Started her up and got the old smoke and soot out tailpipe worse then what ive seen on any car ive had. Took her out for an hour of redline driving to help computer adjust itself. Shut her off now she wont start hot or cold. Turns over. Good battery. Starter sounds good. Gets ready to start then BAM!!! Ita like the rotors hit a brick wall. Shakes whole car right and left. My guess is clogged cat. I guess its not letting out exhaust fast enough and the back pressure kills it. Ive read diy about knock out the internal peices of cat. Ill be doing this tomorrow unless someone has a better idea for me. Your advice is appreaciated.

 

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