I would search around the area directly by the spare tire.
Once the 911 entered the 997 series build cycle, Porsche decided that to save weight, the spare tire, lift jack and lug wrech, would be removed from the parts installed in the front trunk and replaced with a can of tire sealant and a 12V air compressor. Perhaps they thought that since the new tire pressure monitoring system would allow you to detect low inflation pressures, the tire sealant would help restore enough usability in the tire to get you to a repair station before a major failure of the tire. The tires, currently approved for use on Porsches, are designed to be more durable in case of a puncture, but they are still made of rubber.
Porsche 911 because 911 has more ecceloration
Porsche 911 starts from....$85,400 to........$172,100
under the front hood, under a battery cover just beyond the spare tire.
The 2001 Porsche 911 has 24 valves.
The 2003 Porsche 911 has 24 valves.
The 2002 Porsche 911 has 24 valves.
The 2006 Porsche 911 has 24 valves.
The 2005 Porsche 911 has 24 valves.
The 2009 Porsche 911 has 24 valves.
The 2004 Porsche 911 has 24 valves.