* Under the hood: Materials might be placed on the firewall (between the engine compartment and passenger cabin), under the hood itself, and possibly around the engine.
* Inside the doors: Doors often have sound-deadening material inside the door panels.
* In the floor: Sound insulation might be applied to the floorpan, particularly under the carpet.
* In the trunk: The trunk may have sound-deadening material.
* In the roof and pillars: Some sound insulation may be integrated into the headliner and pillars.
To find areas with significant sound insulation, you'd need to visually inspect these locations after removing interior trim (like door panels, carpets, etc.). A shop manual for your specific year and model would be the most helpful resource for identifying the exact location and type of insulation used. Without access to a manual, there's no way to pinpoint a single "right" location.
