I purchased a 2008 EX three months ago. I have another vehicle I still drive, so I have less than 300 miles on my Element. Three weeks ago my tire pressure warning light came on, so I aired up all the tires. I thought it strange that I had to air brand new tires on a brand new vehicle then because in the past, I rarely have to air my tires, even old ones, but maybe once or twice a year. Today one of the back ones was down from 35 to 14. What is up with this? I am driving fromm Phoenix to Chicago next week so I am really concerned now. Any advice?