2007 Suburu Forester snap crackle pop sounds

Recently bought used 2007 Subaru Forester whose engine is still under warranty. When ever I turn off the engine the car continues to make a snap crackle pop sound for about five minutes. The hood is not hot. Besides this the car seems to run fine. The dealer says not to worry about it although he couldn’t tell me exactly what it is. Thanks. Wendy

If you listen closely, you will almost surely be able to trace the noise to the underside of the car. This is because the cooling of the exhaust system–which begins very quickly after shutting off the engine–leads to noises as the various exhaust components and their connections cool at slightly different rates.

This phenomenon is actually very common, and almost every car that I have ever had–beginning with a '66 Ford Galaxie 500–has exhibited this trait. On some cars, it is obvious from day one, and later may be diminished. On other cars, it may only show up after a few months. Either way, this is definitely not something to be concerned about. It is not dangerous, and is not a defect.

Thank you for helping me feel more confident. W

My 2001 Forester makes the same noise, so did my old '99 Legacy.

…as do a significant percentage of all of the cars on the road…