Tyre pressures!!

[Haylzbrooks]

I've got a mini cooper & they dont have the mini run flat tyres on it, they have 18inch tyres on them. I've had the car for about a year & it's always had these tyres. But recently (past few months) the tyre pressures just keep going down really really quickly. Every week I'm having to pump them up & usually they're on as low PSI as 5! Last week I got 'eggs' in 1 of my front tyres & thus had it replaced. But even this new tyre is going down within a week & you can visibily see that its quite flat!

Does anyone have any ideas as to what this could be!? I did originally think I just needed all new tyres, although the fact that this new tyre is still going down quickly seems to suggest otherwise ?!

[Angib]

If your alloys are corroded enough, that can cause loss of pressure - I have had that before, but the appearance of the alloys will be pretty bad by the time this becomes a problem. The corrosion prevents the tyre from making an airtight seal to the rim.

If you've got the lacquer/paint on the alloys lifting/flaking off at the rim, then this could be the problem. It would explain how come a new tyre has the same problem, but I would have expected to tyre fitter to notice and mention the corrosion, if it was bad enough to do this.