I was driving my car today and i was coming out of a turn onto a straight road. So im driving and i let the rpm go up at 4000. as soon as the car shifted i heard a LOUD pop, like a balloon popping. Any idea what it is?

THanks

 

Btw i drive an 08 TL

 

it may be backfire, do you have any modifications on the car?

 

nothing yet. I bought it back in January