Weird engine thump. WTF?

[mortimersnerd]

Was idling at a light at the end of an on ramp and got a weird "thump" or deep pop from my engine bay on my 2008.5 MS3. Must have kicked pretty good because I saw the hood move. Everything looks OK on inspection. Sort of sounded like a deep backfire. Car is stock (other than wheels). Any ideas?

 

[Super Unique]

sounds like a backfire, I would open the airbox and inspect for any damage. As long as you don't see any obvious damage, and it isn't throwing any codes, I would check all the fluid levels and keep an eye on them more than usual for a couple weeks before assuming all is well.