misfiring
 

The car is not throwing any codes, on the dash nor readable to code readers. but this afternoon right before i turned into my neighborhood as i was slowly accelerating the car felt like it misfired like crazy. it would not accelerate. after i let off the gas it went away and i could speed up again. this is the first its ever happened. 2010 with 63k miles. just got tuned by uprev about a week ago. also have injen intakes, FI HFC and topspeed catback. any ideas on where to begin? flashing the ecu back to stock perhaps?

i just gassed up today, perhaps i accidently put 87 in. i dont think i did but thats a possibility i suppose

Without a code it's tough to say what happened. Car feels normal now? Put some more miles on it and if it happens again go back to your tuner.

i had it etuned by Z1 motorsports. i havent driven over 3k rpms when it has happened. it happened very quickly a few other times while slowly getting up to speed. it felt like the brakes cut in sharply for a half second then went away. it was only that one time where it was very bad. i havent noticed any kind of pattern. seemed to do it while it was hot and cold.

Sounds like you have a coil pack going bad. It will throw a code, just give it time.

^^ Agree with you on this one. Just keep driving until it happens again and or until your Z throws a code.

I have not driven the car yet but it is now throwing the p0300 code. Random misfire. It is idling at 1 k rpm

Yeah that loud bang, now misfire code definitely ur coil pack.

How would I know which one. The code is a random misfire not cylinder specific

I'd first look for any outward signs of damage to the coils - bulging, charring, &c.

An ohmmeter may tell you which one is acting up but, if it is intermittent, can be difficult to catch.