I have a 2011 forte sx sedan and it has a knock just the same. It has been making noise since the second week but it also has an even more annoying problem then the knocking. Since the third day of purchase it mainly does it after it's been running awhile but right when I start to push the throttle there is a chirping sound coming from where the clicking is. It is mostly the beginning Portion of pushing the throttle, but also when the car is downshifting to a stop. It is getting so bad that it is even doing it at an idle sometimes. I've taken it in a few times now, but service department claims they can't hear a noise. When i originally took it in, they didnt know what it was and was waiting for kia to tell them something. This isn't the only car brought there with the same problem. I took it back a few days ago, and they are saying the noise is "normal" and they are just trying to sell me a new car for more payments! Sounds pretty Asinine to me! i love my car, but hate paying $400 a month for a vehicle that makes more noises than my 89' cherokee I bought for $400. Not sure what the next step is, since I can't even get it in for documentation. Is there anyone else that has the chirping sound?