So I was driving home, and on the highway ramp i decided to shift the knob to SS mode and proceeded to drive on first gear. I then went to second gear automatically and i put my foot down on the gas pedal while going up the ramp, at about 6000 rpm, my CEL flashed for a few seconds and then turned off. I kept driving and everything drove normally, i got home and proceeded to try to find any odd smells or anything that might signal any issues. There was nothing.

I had this happen to me before when i downshifted on SS mode. I brought it to a mechanic last time and he couldnt pull any codes. I did some research and some people are suggesting its a false misfire code? Do you think this is it? Or is it that my cat has issues?

HELP!

 

Happens to many under heavy acceleration, no problems.

 

Trying to catch up to that Hyundai again?

 

Had the same thing on my 07 TL. It is easy to trigger it and find out what the codes are.
You don't necessarily have to floor the car. Simply, put it in manual, drive up high rpms and keep it there until cel flashes. Now you have to options. If you have OBDII reader, plug it in and read the codes. If you don't have the reader, repeat the whole procedure and this time CEL will flash and stay on.
Now on your NAV (if you have one) go to messages and look at the codes. There should be one P0300 and possibly 2-3 more P0301-P0306.
You can than swap the coils and trigger CEL again and see if same cylinders came back. If not, then it is most likely your ecu that needs to be re-flashed.