So what did you find? I seem to have the same problem, and the passenger seat is much more comfortable for me due to the lack of lumbar
Well I finally got to try out the passenger seat on my car and attempted to compare it to my driver's seat. Lumbar seems to be about the same when I inflated it all the way and then deflated it. Meaning, even fully deflated, it still seems like there's still some air in the bladder. So I'm wondering if even fully deflated, it doesn't remove all of the air out of the bladder? I also tried pressing against the lumbar on the seat while holding the deflate button, but it didn't seem to help eliminate anymore air out of it.
I swear that after I fully deflate the bladder, it feels like it's inflating a bit because I start noticing some movement against my lower back. But it might very well be my lower back adjusting to the lumbar not pushing up against it. But at the same time, when fully deflated, my back feels pretty comfortable for about 10 seconds.
I then tried to listen to the inflating of the 2 lumbars when pushing the bottom button, the top button, and the forward button. You can definitely hear the pumps inflating. I couldn't really notice the seat material getting larger, but I wasn't staring at it at a good side angle. When deflating, the noise is much quieter; again, I don't see much movement in the seat back/lumbar area. Also, when fully deflated, I don't hear the inflation pumps starting again. So it doesn't seem like the issue is after you fully deflate it, it starts to inflate again. I think the issue is that the bladder just doesn't fully deflate.
I'm wondering if there's some valve under the seat that could release any additional air in the bladder. Like most of you, I could have sworn the seat was far more comfortable when I first took delivery and before I played with the lumbar buttons.
I need to bring my car into the Dedham, MA Service Center this Friday. I'm definitely going to bring this issue up. Because now, when driving, I'm finding myself constantly inflating and deflating the lumbar in the hopes that it goes "down" all the way.
-- Cintoman