Do I need the whole TPMS sensor to fix air valve?

It likely hasn't had time to be certain that a sensor is missing. A few miles on the spare will fix that. Maybe faster if you leave the flat tire in the hatch area and it picks up the low pressure from it.

 

The TPMS system should immediately alert if there is a low pressure at one of its sensors. Maybe breaking the stem caused another issue with the sending unit. If a sensor is missing in action, the system tried to communicate with it for about 20 minutes of continuous driving before it gives up and triggers a warning light. After all, it is logical that your tires are supposed to be on the car

 

As Mendel said, spare does not have TPMS in it. The low tire pressure warning light, looks like below should come on soon after car starts.

 

For removing the remaining valve caps:

First off, it might be good to remove the wheel cover, grab in a couple of openings, and yoink quickly. Hopefully will pop it off.

Then to remove the caps, if possible, restrain the valve stem from turning, by clamping it with a pair of bent tip pliers, below the cap, just tight enough to restrain it from turning. Then with a second set of pliers (or a ratchet wrench and socket, if you can find the right size, might be 3/8" or 10 mm), grip the cap and try to break it loose.

If the valve cap is just metal, carefully applying heat with a propane torch might expand the cap enough to help break the bond.

Video encompassing all of the above:

@kikik, whether you or tire shop, I'm guessing this is how it'll get done. Again, they really should not be selling these metal caps; they should be banned.

 

As suggested above, something might have gone wrong with the sensor unit sending signal to car's control unit. It may take longer than 5 min for the car to realize that there is problem with one of TPMS. Of course, this is a problem on its own. Registering TPMS malfunction should be immediate if it is there to warn you in an event of lost tire pressure. Have them checked out at wherever you are planning to take the car for repair.

BTW, the thing flow out and hit you is the core of stem. That should not be the part of TPMS sensor itself. Actual TPMS sensor is the black bottom part of the last figure you posted. Wish you the best for repairing your tire and.

At the least some warning label especially in areas with winter road salt.

 

Or they could redesign them with plastic/silicone covered threads or something. But as long as people buy them, they'll keep making them. Like Doritos. Just because it's crap doesn't mean they will be banned. People need to stop buying them it's that simple.

 

If you apply heat very sparringly like with a bic lighter, not a torch it should be okay. They idea is to heat only the cap and not let the heat go further.

I like the dremel idea. But also very carefully cut with the slowest speed and across the path of threads and I would try to not go all the way through the cap, just enough to weaken it and then take the pliers and squeeze such that the cap would break where the cut/score mark was made. I would also try all manner of penetrating oils. Liquid wrench and such. It may just work that way.

 

Yeah I would go OEM. Is the OEM quote from dealership, or both quotes from tire shop? If tire shop, are they confident they can get the new sensor intitialized, recognized properly by the car. Hope it works out for you.

I'm almost assuming it must be tire shop for both quotes. A dealership, I'd guess they'd be asking around $200??

See too if tire shop can remove the other valve caps.

This is my weak spot:



I walked by a display of them in Rona yesterday, it was tough...

 

I would definitely go with AFTER MARKET with TWO piece TPMS and stem system. That way, if you have to change the stem, you do not have to buy new TPMS. BUT if the LOOKS is important, and you really want all 4 stems to look the same, then go with OEM. However, there are aftermarket TPMS with aluminum stem that looks almost identical to the OEM if that matters to you, but rubber stem is better against salt corrosion and cheaper.

 

Sorry, I typed too fast... I corrected it. Read my comment again.

 

I was thinking about this too, similar story:

Metal valve stem caps. Ugh... | PriusChat

People are just wandering around automotive accessory aisle, looking for something nice for their car, and pick up some dressy metal valve caps on a whim, they should ban these.

 

Yeah, I remember this thread. OEM TPMS comes only with aluminum stem. It does look nice, but for winter road salt area like OP lives, time tested rubber stems works much better. IMHO

 

GO FOR IT. It means they have to order OEM TPMS, but have aftermarket one in stock.