I've been having this issue with my G35 tire for a while now and just wanted to chime in thoughts on what the issue might be.

I had all 4 tire on my G35 changed some months ago but had been consistently losing air in one of tire. Every week the TPS indicator would set off and alert that one of the tire is below pressure. Usually 5-6 psi of pressure is loss in the tire as the week goes by without filing the tire up with air. I had the wheel and tire checked by two different tire shop and they all said that it was fine. I also had the rim reconditioned at a wheel store to fix any rust that might be causing leak, but this leak is consistently happening. It has been a pain to always air the tire up every week to optimal psi.

I'm wondering if anyone ever had this issue and if so, how did you fix it? Also, could it be the tire or rim that's causing the leak?

 

They need to tie it down inside the dunk tank and let it sit for longer since it's a slow leak.

 

5-6psi in a week is a pretty slow leak, so it may be hard to find.
I would take that tire off and spray windex or soapy water along the edge of the rim (where the tire rubber meets the rim) and check for punctures/leaks. The windex or soapy water will bubble up at any of the leaks. Over-inflating will help with this too. Check the valve stem and core while your at it.

 

Yep, had to do this with one off my wife's car, turned out a pinhole leak had developed on the inside of the wheel, which is why the dunk tank and soapy water weren't showing anything. Since it was under warranty we had taken it to the dealer, ended up with a brand new wheel for it.

 

Thanks for the advice. Well back to the tire shop we go again, hopefully this will be the last time for awhile.

 

Usually it's a bad seal on the rim, or a leaky valve stem. They should clean the rim with a tool, or replace the valve stem, and reinstall your tire.
If you live in an area with a lot of construction it could even be a small nail or screw that's embedded in your tire that won't leak dramatically but will cause a slow leak over time.

 

They should also REPLACE the schrader valve inside the valve stem. Most reputable tire shops replace them any time the tire is dismounted since they remove it to let the air out but some shady shops will reuse them, that little rubber seal is not really intended to be reused however, you can also get a defective seal on a brand new one. You can ALSO get metal valve stem electrolysis wear but you can usually see if it's pitting inside the stem (if you look for it).

 

Sounds like OP fiddles with the valve A LOT
Refilling weekly .... Loosey goosey ... seal's prob DONEzo
Take a 12mm and tighten
IF you break it .... Aftermarkets are cheap bro

 

So I just got new tires and guess what same problem as OP

The seal on the sensor was bad. He tried taking off the sensor but advised not to because in his experience it always breaks

He just tightened it . From the outside. It worked.

Try it.

 

I feel that it could be your wheel (rim) that's leaking. My 2010 M35x has one wheel that's been leaking since I owned. I know they did a recall on it, but didn't manage to correct it. Through all the tires I've owned it's ALWAYS been the same wheel leaking, a slow leak. The tires are good. I've been busy working without much time to correct this issue, but I'm going to address this annoying issue next time I have time off. They placed some metallic gray stuff around the stem and it's no different. I'm just going to ask for a different rim with no leaks.