Car rattles when stopped

My wife’s 99 Saturn SC1 rattles badly when it comes to a stop, particularly after it’s warmed up. Only when it comes to a complete stop, not a rolling stop. It sounds like it’s coming from the underbody, possibly toward the rear. Any idea what’s wrong?

Check for loose/detached/damaged exhaust system hangers. Just be sure to do it when the exhaust is completely cooled-down, such as first thing in the AM.

If all of the exhaust hangers are okay, then my next suspect would be a loose/damaged heat shield on the exhaust system. While these are not usually toward the rear of the car, you have to remember that unitized bodies tend to “telegraph” noises so that they sometimes sound like they are coming from a different place.

I’d suspect a loose heat shield somewhere on the exhaust system.

Another possibility is a damaged exhaust hanger, allowing the exhaust pipe to contact the underside of the car.

I would suspect a loose heat sheild also.