I'm not sure what these items are called.... the cap that fits on the tire valve stem that indicates proper air pressure... one of mine was bad from the factory I think. I took it off to look at it when my car was a few days old and, when I screwed it back on, air pressure leaked from it. I took it off and replaced it with a standard cover.

I guess I'll need to pick one up at the dealer. Anybody else have the same problem? Any creative solutions? I think mine is stuck open or something.

 

Not sure what you are talking about, the caps on the tire valve stems are not pressure sensing.

If you remove one and the valve stem is hissing, leaking, the valve insert needs to be replaced. I would do this as soon as possible as the caps are not designed to maintain the air pressure and you will get a flat.

Maybe your dealer added them to your car if they do show pressure as a freebie.

 

Hope they didn't charge you for them. (My Nissan dealer called them TIREXM and they were a $120 dealer add-on)
Is it the green, yellow, red clear cap with chrome base with "32" on the clear area?? If so, You can pick them up for $10 at Auto Zone etc for a pack of 4. I've got them on my Z71 Suburban-wife likes them.
They work great for about a year then the spring inside gets weak and your tire pressure will have to drop about 6psi before a color change takes place. They obviously shouldn't leak when tight, but as you unscrew or screw on you will hear a slight hiss until tight or completely off....

Smitty

 

Yep... that's the exact description. I guess the dealer put them on. I think I'll just ditch the lot of them since I already own a tire pressure gauge.