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My car’s tyre pressure warning comes on during cold mornings, then disappears after about 20 minutes of driving. The door sticker specifies 33 psi for cold tyres. Before setting off, my gauge reads around 29–30 psi across all four tyres; after the drive, the readings are closer to the sticker value.
Should I adjust the pressure using the morning readings even though the warning clears later? I’m unsure whether “cold” in cold tyre pressure refers to the outside temperature or how long the car has been parked.
Also, what pattern would suggest a slow puncture rather than a temperature-related pressure change? All four readings are fairly similar, but I don’t want to assume that a warning which goes away can be ignored.
