Whenever I drive next to a wall or parked cars,I can here a chattering noise. It is loudest when going through 1st and 2nd gear aggressively. I am chipped w/ injectors and Im not sure what it could be. I figured I would ask some of you guys before I take it in and argue with the dealership. Its not a constant chatter throughout the whole gear, but more of an on and off chatter when going through 1st and 2nd. I also wonder if its something in the engine bay that is rattling. Please Help!!!!! It's buggin the crap out of me. I could be in 2nd gear crusing around 2500-3000k rpms. then when i floor it, i will here the chatter, chatter will last for about 2 seconds, then it goes away as i shift to third. It always happens when i floor it.