My car is in the shop so I got a loaner (2014 Jetta wagon, ugh). After leaving the lot with the loaner the dash "check tire pressure" lite came on. OK, I go to the nearest gas station and am reminded that air isn't free anymore. OK, whatever. The gauge on the air unit is a piece of crap and I guess at 32-34, maybe 36 psi. My pressure gauge is in my car which is the shop (VW dealer, more on that fiasco if you want to know). So, I head home and the dash lite is still on. Tire looks inflated so I don't worry about. Today I run some errands, get home and see a bubble on the sidewall. Luckily, Les Schwab (local, well respected tire chain) is still open and they swap it with the spare. Could I have over inflated it and just by driving around town for a half an hour (no pot holes or curbs encountered) caused the bubble? I can't believe it so asked the tire store guy to print out a work order to document that I did the responsible thing with what could have been a defective tire. Thoughts?