Last week, I met a Miata owner and observed that he was lugging around a rather large 12-volt compressor in his trunk. I asked him why, when the car already comes with one in the Tire Service Kit. He stated that the manual shows the kit’s compressor hooked up with the sealant bottle in-line, and he wanted a compressor for just adding air, since his TPMS light keeps activating. I think I was finally able to convince him:
- that for those of us that do not have actual TPMS sensors, false alarms are quite common during spirited drives
- that the factory supplied compressor can also be directly attached to the tire valve stem without the sealant bottle in between
As proof that the compressor can be used for tire inflation, the Mopar instructional video recommends checking the pressure using the compressor’s built-in gauge (as shown in the photo above), by attaching the compressor directly to the valve stem, approximately 10 minutes after filling the tire with sealant and spreading the sealant throughout the interior of the tire by driving 40 – 50 mph. If the gauge indicates that the pressure has fallen below 29 psi, use the compressor to bring the pressure back up, which hopefully provides you enough time to proceed to a tire servicing location.
Please understand that the sealant bottle (good for a single application) should only be used as a last resort if a puncture leak is suspected, and that you might consider purchasing a tire plug kit that can be slipped into your Tire Service Kit as a preferred alternative to the sealant. Plugs can serve as a permanent fix to a “clean” puncture (such as a nail), vs. the sealant repair, which should not be counted on for more than a day or two. Many experts advise having a patch adhered to the interior wall of the tire at the location of the plugged tire puncture, especially for those of us without a spare tire to serve as a backup, but if you choose to do so, at least it can wait for a convenient time and place.
Be aware that you should address an abnormal tire condition ASAP, rather than driving on, so that you won’t unseat the tire from the wheel rim. As long as you didn’t have a blowout, not only will the quick reaction help you avoid destroying the tire and the rim, but it will also allow you to re-inflate the tire with the compressor, which will be highly unlikely after the tire breaks away from the rim.