Thats another way of saying very slow leak.

Its just one alloy on my wifes very old Focus. Over a week it looses about 10psi. The tyre has been changed and it still does it. No obvious damage to the alloy. The tyre place I use say some old alloys just go like that.

Anyone else had the same problem or found a fix?

Did they bear seal the rim? If not it will be there, it's also possible for the valves to stick in cold weather. 

 

I've also had cracked rims too.

It's often corrosion round where the tyre bead sits, if its not to bad it can be sealed with sealer, but if its bad it will need cleaning properly, also the other point that suffers from corrosion is the valve seat.

I took a good look at the rim when they took the old tyre off it looked to be good and clean because I mentioned it going down they used some sealer on it. Still no difference.

Valve was replaced.

 

I had the same problem with an old Focus and it was definitely the wheel in my case.

I'm not recommending that anyone else does this but I bought an small aerosol of Tyre Weld, put that in following the instructions and after a couple of days the Tyre pressure stabilised and it did not lose any more air.

That car did not have  TPMS Valves and the Tyre Weld manufacturers do not recommend it for anything other than a temporary repair to a Tyre, but it saved me the weekly chore of filling that tyre with air.   

Once again this is not a recommendation by me.

Best way to cure a leak that's not detectable is to fit a tube.

3 hours ago, Tizer said:

I had the same problem with an old Focus and it was definitely the wheel in my case.

I'm not recommending that anyone else does this but I bought an small aerosol of Tyre Weld, put that in following the instructions and after a couple of days the Tyre pressure stabilised and it did not lose any more air.

....

This had crossed my mind there is even a can of Tyre Weld in the boot ready to try, however I was just thinking of putting a small amount in, but wondered if the would be enough to coat the alloy. My guess was it would be thrown out and coat the tyre? Still up there on the list of options.

3 hours ago, Milkman said:

Best way to cure a leak that's not detectable is to fit a tube.

Can you still do that? I can remember years back when that was the answer to a lot of problems but didn't think you could do it on alloy wheels?

2 hours ago, Nick Charles said:

This had crossed my mind there is even a can of Tyre Weld in the boot ready to try, however I was just thinking of putting a small amount in, but wondered if the would be enough to coat the alloy. My guess was it would be thrown out and coat the tyre? Still up there on the list of options.

I took the in for a penny in for a pound attitude and used a whole small tin for my large Tyres after letting half the air out of the Tyre. The one I used was a water based one and it comes out like a hair mousse. I'm not sure if you can stop it or not once you start.

2 hours ago, Nick Charles said:

Can you still do that? I can remember years back when that was the answer to a lot of problems but didn't think you could do it on alloy wheels?

I not sure if anyone makes Innertubes for modern low profile Tyres now and even if they did I don't think any reputable Tyre Fitter would risk fitting one yo a customers car.

I also don't think that an inner tube can be fitted in low profile tyres but on 'normal' tyres you can, alloy wheels are given to tyres deflating slowly, I have had Discovery's with alloys and have always had inner tubes fitted and the advantage of that, like the possibility of this exercise, saves a perfectly good tyre that has a wall puncture.

If I try the tyre weld and that doesn't work anyone know how easy it is to remove if it doesn't work so I can then try an inner tube?

As it is the tyres will probably out last the car.

I've had this issue too. All but one wheel leaks where I have to check and pump them up each week.

I've had them cleaned and refitted but still the same.

How much does it cost to replace the wheels nowadays?

Can you get second hand ones that come with some sort of guarantee?