[Stevieno1]

In the 2 months I've had my 2018 M2, I've had 3 tyre pressure alerts. The below pressures are in the order pass front, drivers front, pass rear, driver rear:

1. Pumped up tyres at the petrol station, the air pump gave me readings of 30, 31, 33 and 35 psi.

2.1 iDrive gave me cold tyre warnings of 28, 31, 33 and 33
2.2 6 miles later when warm they showed as 30, 35, 35, 35
2.3 Petrol station air pump showed 30, 34, 35, 35

3.1 iDrive gave me cold tyre warnings of 29, 31, 33, 32
3.2 6 miles later when warm they showed 31, 34, 35 35
3.3 *Haven't been to pump then up yet*

What is the +/- the warnings will trigger, does it care what the actual pressure is or is the logic just it will ping an alert when a tyre drops -5 psi from the last reset? I'm presuming its when cold this matters only?

From the above I really don't see a massive issue, whenever I'm pumping them up I make them 35 psi all round. A friend has suggested looking at the above readings it could be a faulty valve in the passenger front tyre given its an outlier compared to the rest. The warnings are going off almost every 2 weeks like clockwork which makes it unlikely the sensors are faulty (as he reckons it would be more sporadic).

My previous car is the only one I've ever had before that had tyre pressure monitoring, and it would go off around every 8 weeks which I didn't think was bad, but surely my M2 shouldn't be pinging every fortnight? Any thoughts welcomed.