[Tim G]

Does anyone elses bolsters hold pressure for any period of time?

My car is only 5 years old, but neither driver or passenger seats hold pressure. You pump them up full, and they will be obviously smaller 5 minutes later, and back to fully deflated within 20 mins.

Ive taken the drivers side seat back off to take a look. When fully inflated (and particuarly with still with your finger on the inflate switch) the pump/valve on the drivers side (pictured) can be heard leaking air through the round area with the small rubbery bit inside. I have no idea what the purpose of this is for, although I did wonder if it is a safety mechanism to prevent you from over inflating the bladders, so this might be normal. It is impossible to pinpoint any leakage anywhere without full pressure, as the deflation is gradual.

I am sure the bolsters in my previous 1 series stayed where they were put permanently. I therefore find it odd that not one, but both of my seats deflate in a short preiod of time, unless this is normal on the 3 series!?

Pic of the valve for reference

[Dann]

I haven't noticed mine going down at all. They still feel as hard as they did when I pumped them up 4 weeks ago

[Ess]

Doesn't sound right to me Tim. As far as I can tell, mine stay inflated

[Tim G]

Hmm. As I suspected. Gonna test out the passenger side one again today just to double check if it loses pressure as quickly as the drivers one.

[Tim G]

So I checked both front seats again today and neither hold their pressure. Very odd as I doubt either of the seats have been reguarly adjusted by their previous owner, so it wouldn't be due to wear and tear!

Very odd and double annoying as I was planning on swapping the valve from the passenger side to the drivers side so at least the drivers worked!

Having had a decent look at the setup its hard to see what would perish, unless it is the seals inside the valve that go over time. Cars only 5 years old though!