I turned on the car and found out that CEL came on!!
So, I plugged in a Cobb AP and got an error code PO300-Random Misfire.

I realized the RPM did not go below 1100rpm at idle. (it used to be around 800~900 rpm below 1k rpm)

I test drove it and heard weird noise once it got moving and I didn't hear anything weird after that. So, I resetted the ECU via my Cobb AP. It didn't come back on and I've not heard anything weird so far.

What should I do next? Should I bring it to a dealership?or I can forget about it and drive until it comes back on again.

But, I'm not really willing to bring it to a dealer if possible because I have a Cobb AP(Stock style map), test pipes, stillen g3 intake, and catback exhaust.

 

idk about the misfire,but I do believe test pipes are letting out alot of exhaust.you could just be tripping the ecu to show that code.what type of gas are you using,you could have gotten bad gas,especially a misfire.

 

I've heard numerous posts about triggering CELs with that same setup. What kind of test pipes do you have, and do they have built in non-foulers?

 

GTM test pipes w/ J tube.
If it were testpipes, the code's supposed to tell me catalyic converter code not the misfire...

 

My test pipes threw some codes do to the o2 sensors , guessing they've gone bad. I have the gtm ones as well, it's been about 6k miles since I've had them on.