I've never tried this, but several forum members have and they report that the pressurized container has worked OK for them.

When the car sits still for more than 15 minutes the tire pressure sensors go into a sleep mode and only transmit once every 60 minutes to save their internal batteries.

When you start to drive faster than about 20 mph there's a switch that senses the rotation of the tires and the sensors wake up and begin to transmit once every minute.

So....if you've got the sensors sitting in a pressurized container that is not spinning around, the sensors are only going to transmit once every hour.

You need sensors for 2 main reasons: 1) with the stiff sidewalls on runflats you don't get any handling feedback when the tire loses pressure while going straight, and you'll wonder why you ended up in the guard rail on the exit ramp when a sideload builds up; 2) you may have problems turning off AH or go into Comp mode, and you can have big problems on a road course when the car pulls power (limp mode) and puts on individual brakes because it thinks you're driving too aggressively on a flat tire.

Whether once per hour is enough to keep from having problems associated without having sensors mounted in the wheels, I dunno!?!?

Bob

 

GREAT FEEDBACK....thanks

 

will not work after 20 minutes or so as the computer scans for them about that often and if they are not moving, will not work. Well known among the VIR track crowd. Only solution is put the sensors in the wheels or get with Phoenix performance they can reprogram the computer...only ones i am aware of.

 

I've heard that the company you mention has come up with a way to bypass the TPMS.

You can disregard emissions requirements and run with no Cats (if you can pass your state's inspections without them, or your state doesn't inspect).

You can disable your airbags.

You can drive without fastening seatbelts.

So you can also disregard the law and get Phoenix to bypass your TPMS.

Federal law requires tire pressure sensors and a TPMS on all 4-wheeled vehicles less than 10,000 lbs.

I don't know, but I bet that for liability reasons they may not be real interested in bypassing the TPMS in a car that is driven on the street. You haven't seen them doing much advertising for it - probably because they mainly just do it for cars that are only going to be track cars.

Bob

 

ok..your point? get the sensors in your wheels...whats the problem

 

well before, what was it, 07, all cars weren't required by law to have tpms, and im pretty sure cars worked just fine without them. are they a nice safety feature? yes of course. but not NECESSARY.
although i don't know what the debate is, the sensors are $148 for a set of 4 from tire rack.
to the OP:
if you don't have a spare $148 lying around for peace of mind, then i don't think you should be modding your car.

 

Like I said, you don't need airbags, Cats, seatbelts, or a helmet when riding your motorcycle in order to make the vehicle go down the highway.

However, if you're driving on runflats, tire pressure sensors are absolutely, positively, 100% NECESSARY to safely operate the vehicle!!

I had a slow leak while driving down the interstate about 40 miles from home several years ago. I would never have known it without the sensors sending info to the TPMS and the tire pressure being displayed on the DIC. You just don't get any handling feedback while you're going straight down the highway.

But, if I didn't know the pressure was at almost zero by the time I got off the interstate, and I took the off-ramp in my usual spirited manner, I may well have ended up in the guard rail when a sideload built up and the tires let loose unexpectedly.

Look on the side of your runflats and you'll see a statement on there about you must run sensors in the runflats. That's a liability thing required by the company's lawyers.

Same with a company disabling or bypassing the TPMS - I just don't think they're going to do it for a street driven car.

BTW, here's a synopsis of the Federal Law concerning sensors:

Bob