I've had my G37 for about 4 weeks now. My 2nd day of driving (about 120 miles on the odometer) my front driver side tire blew out. After much complaining, the Infiniti dealer replaced it for me for free since it was obviously defective. Problem is that for the last 3 weeks that same tire has been losing pressure constantly. Ill fill it up to 35 PSI and by the end of the week it will be down to 30.

I cant figure out what can be wrong, and whether the initial blow out and the pressure loss is related. Faulty valve stem maybe? Could there be a problem between the seal between the tire and rim?

 

take the wheel off, make sure it isn't damaged

check the valve stems

you could put it in a bucket of water or something and look for bubbles

 

Same things happening to my rear left tire, I'm not sure if I'm cornering too hard or what but ONLY that tire is ever down to 30 the rest are usually at 34.5-35. I check my tires weekly.

 

+1 for checking for damage

 

yeah that sounds like maybe a bad valve or somthing u mite wont to take it to the dealer to check it out