Pressure reading tire valve caps?

[ThinkOfTheChildren]

I wanted to grab some of those valve caps that warn you of low tire pressure. Seems like there are a couple varieties, but I've read a few stories from people who got flat tires from faulty caps.

Are there any reliable ones out there, or is the whole concept flawed?

 

[Dr. Mudd]

DON'T get the ones like I tried! One of the four I bought new and then used right away leaked and caused me a lot of grief until I found out why my tire was going flat or close to it. The worst part was the leak seemed to be intermittent. They were made by Victor and had a green read-out visible mark. I tried to return them, but I had not saved my receipt so I was SOL. :thumbdn::thumbdn::thumbdn:

 

[gadgetgeek]

flawed concept, basically they depress the valve core to allow air into the cap body, a diaphragm pushes against a calibrated spring giving you a reading. the problem is as soon as the diaphragm leaks, the tire goes flat. they also only read below their rating (32 psi or lower for example) I had some caps for a while, and found that they would show green all the way down to 25lbs, not good for 32psi. I check the tires on about 10 cars a day (30 go though the shop where I work) and I find about 2 cars with over pressure tires. something your caps won't tell you. I recommend getting in the habit of checking tires with a gauge that has at least 2psi graduations. little bit of time, lots of saved cash in fuel, tires and repairs. just the thoughts of a auto service goon.

 

[J.S. Carter]

yea defnatly waht gadgetgeek said,

 

[ThinkOfTheChildren]

Thanks, I appreciate the info.

In lieu of getting said caps, what product(s) would you guys recommend that can be kept in the trunk to inflate tires? I always keep a can of Fix-a-Flat around, but is there something I could just plug into the car for juicing up the tires here and there when they aren't actually damaged?

Yes, I realize most gas stations have tire filling setups, but I don't like relying on running into one. I also don't have a garage and live in a small apartment with no storage so a full-sized compressor is pretty much out of the question. Anything portable that does a halfway decent job works for me. I.E. I need it to be able to inflate back to 32 psi, but I don't need it done at the speed of light.

 

[gadgetgeek]

walmart type stores (I don't know what the american version of Canadian tire is) have air compressors that can be run off of auto 12v power. they do take a long time, but small enough to be worth having. look around and find a high quality one, you'll pay more, but you won't have to re-rig the hose if the crimp is bad or try to fix a broken power wire. I bought my mom a set that came with highway triangles, and a hard carry case for her van. and they work for basket balls and such. or just get a good large bike pump, cheap, and a workout, but its been done before.

just a thought, fix-a-flat is good, but if it doesn't quite do the job your still out of luck. also it prevents you from patching the tire later, which adds the expense of a new tire. look into getting a valve core wrench, I've seen lots of slow leaks that were fixed simply by tightening the core.