when i turn off my car. weird noise?
 

fresh rebuild. N/A s4. When i turn off teh key i hear like 2 tiny bumps at teh end on teh left side of the car? what could it be? also when i was driving the car for about 3 hours at 65 miles per hour in 5th gear i hear some bump noises from the rear of the car. could be a tranny mount? is my tranny dyieng? fuel pump?

Does it sound like a loose exhaust rattle?