Buy a tire pressure gauge. Every car owner should have one. Moroso makes a good one that is accurate and easy to use. It's about $45.00.
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'11 BMW 128i 6MT
Titanium Silver, Sport Package, Cold Weather Package, Sunroof, Sensatec
DISA Intake, AA Header, MILV's, Stage FP Tune, VAC Motorsports Quaife LSD, CDV Delete, M3 Upper and Lower Front Control Arms, Powerflex Yellow RSFB’s, "Square" Tire/Wheel Set Up: Michelin PS A/S 3 225/45 17"'s on 17"x7.5" Type 262's