When the outside temperature reaches 80 degrees I get a thump or loud bang coming from under the car. My passenger said they felt it under their feet. I have taken it to two dealers and they could not hear the noise. They put the car on the lift and did not see anything. Their attitude is that they do not hear it so it does not exist. My warranty is up next month. If it is not found I may trade it for a Subaru. Volkswagen repairs can be expensive.