Semi-agree w your mostly agree w @Cheesesteak. Any piece of emergency equipment, even a traditional full-sized spare tire, needs to be serviced periodically. The kind of folks who buy stuff and throw it in the trunk unseen, expecting it to be useful 5 years later are fooling themselves from the git-go.
When I bought a rechargeable jump starter I charged it fully and set a task to check it 4 months later. When my computer alerted me I brought it inside and found it was still full. Waited a couple months, checked it again, and found that after 6 total months (in a benign climate) it was down to 3/4ths. So I recharged it, set a repeating task to check & charge it at 8 month intervals and now it’s out of sight out of mind. My computer will bug me when I next need to think of it. But now I’m confident it’ll be useful to me whenever I eventually need it.
IMO that kind of thinking is the minimum buy-in for everything seldom use. A plug-in compressor may seize, the stuff in a first aid kit will dry out or rot or …, your cold weather emergency blanket will become mold- and mouse-infested etc.
My bottom line to everyone:
“Buy it, dump it in the trunk, and forget it” is a plan to fail. No matter whether the thing has a battery or not.
But you can still get free air at Costco! Close enough to you at North and First!
That said I’m thinking of one of these things. Of course the low air pressure light comes on when the temp drops to low single or negative digits. Makes sense. And topping off in my garage at that point has a special appeal over fumbling with the caps and the hose outside.
I bought one for each of our cars and showed my wife and kids how to use them. Buy at Autozone or O reillys. Plug into the power port. Handy for inflating bike tires too.
The inflater came today - and I’m THRILLED! It is EXACTLY what I wanted for my purposes.
It amuses me to think that someone in Idaho had a bunch of these things, factory packaged, from however many years ago. Works like a charm.
I also feel mild satisfaction at being able to get just what I wanted. Simple, mechanical and old school. And, in the process, getting around today’s tech market which seems to increasingly offer what I personally DON’T want.
I see Dinsdale already got what he wanted but I’ll chime in with my opinion. I don’t like the cheap 12 volt plug-into-the-car compressors. You imagine the failure mode is that the compressor just stops compressing, and I’m sure that happens from time to time, but the three failure modes I’ve seen are: (1) it’s set to compress to a certain PSI but it does so unreliably and you can’t tell whether the tire is properly inflated or not, (2) the plastic insulation on the power wire breaks before you ever use it and so it fails before it is ever used to inflate a tire, and (3) it blows the fuse on the power port (or cigarette lighter), making it worthless when you need it. The last one happened to my Dad and he could never find the fuse to get the outlet to work again. (I assume it was an inline fuse somewhere in the console but I never looked).
For emergency use in a car, a cheap bicycle pump is all you need and it’s always ready to go with no maintenance. Most will inflate up to 90 psi, which is far more than a car tire needs. It would take a while if the tire were completely flat but airing up from, let’s say 25 psi to 32 psi is only around 20-30 pumps and takes no more time than fiddling with a 12 v compressor.
For whatever it is worth - as I indicated in the OP, I always used to use a hand pump to top off my car tires, but for whatever reason, I could not get it to seal on this car’s valve stems. On-line sources claim it is supposed to work, but I could not get it to. No idea why, but as an avid bicyclist, I’m quite familiar with using various hand pumps.
So, if you wish to go with a hand pump for emergencies, be sure to give your pump a rial on your tires first.
Good advice. I’m assuming this is not a problem like using a Presta valve bike pump on a regular car tire valve because anyone using Presta valves would know they aren’t compatible with ordinary valves.
My new bike has Prestas. I’m quite experienced handling both. My Bontrager pump supposedly handles both, and I’ve used it for non-Prestas in the past - including multiple prior cars. I spent considerable effort, including on-line research and attempting to adjust the pump’s connector, without success.
I readily acknowledge that user error is a possibility - but if so, this user was unable to overcome that error.
Sure, user error is always a possibility but I think that’s less likely than a worn out tire pump. My tire pump uses a rubber diaphragm that is pinched by a pair of jaws when I clamp the valve. Over 20 years, the rubber has worn down a bit and sometimes it fails to clamp tightly. It’s possible that the diaphragm used to have molded threads but, if it did, they long ago wore smooth. I could say it’s user error when it occasionally pops off but I’m blaming the pump. It usually works fine the second time so I forget that I should probably get a new one until the next time it slips off.
Just worth throwing this out, but sometimes the spare tire (if you have a full spare) in the trunk gets low, and that sets off the low tire alarm on your dashboard. Even if your 4 tires are inflated, the tire in the trunk can get low.
You need a long cord so the air compressor can reach the tire in the trunk. So make sure you have one with a cord long enough that it can reach all 5 tires on your car.
