TPS (Tire Pressure Sensor)

I disagree. There some of us that don’t always check the pressure. And as time goes on I’m depending on it more and more, (Just like AI... Unfortunatel.)

an example, When a cold weather snap happens, there’s a vehicle where there’s a tire that’s low. And driving with low tire pressure can be an hazard, itmalso affects mileage.

Heres what AI has to say....

“ For every 1 PSI drop in the average pressure of all four tires, your gas mileage can decrease by about 0.2% to 0.3%. This can result in a loss of 1-3% fuel efficiency if your tires are significantly underinflated.“

The savings in fuel economy can be negated by one lead foot episode. The TPS are nothing more than another dealer money skimming idea which will be incorporated into the control to cause even more money skimming when one fails.

This is why I drive a 30 year old diesel 4x4 or a 25 year old corolla, not open to easy fleecing.

Besides unless the tyre pressure is checked with a known good gauge how can the in tyre monitor be verified as good and not off calibration. Can a monitor living in a hostile environment be all ways relied upon?

Sure, Theres so many variable's on gas mileage, maintenance such as oil changes, driving with the windows open, aggressive or poor driving...

As far as TPS, theres a place for it. When you look at the history of owning a car... Or actually the generation that now own a vehicle.

The shift in owner's manuals from "how to adjust the timing" to "do not drink the battery acid". Sure to a degree it’s the complexity of today’s vehicles and the focus on safety… really to not drink the battery acid?

Now i used to do a lot of my maintenance on my vehicles to a point a few years ago I purchased a OBD reader... Not that i enjoy it, it was actually the best part on working on a car is when your finished. For the most part, I actually hated working on vehicles. But the ability to work on a car came in handy when problems occur on the road.

And now, for the most part, I tend to take it into the garage. Especially now being a AAA member.

"And now, for the most part, I tend to take it into the garage" At my age, a lot of that is declining stamina and strength!!! Tomorrow may be the first time I pay to have my oil changed.

known good gauge. That's interesting! How do you check/calibrate an air pressure gage? I have several "good" gages, and they all give slightly different readings! Which one is closest to being correct?

I use the machines at Costco, and find that eventually all of the TPS readings agree. Also a Craftsman digital gauge matches the TPS readings. I’ve seen some TPS sensors 1 of 4 take a half day to come up to the Costco number.

When I see corroboration from 3 independent sources, I tend to believe the TPS sensors are the gold standard, for your 0.5 psi accuracy.

Totally agree with Stef. My wife has a 2022 Volvo. The tire sensor goes off at random. I go to the "offending" tire and find that it is fully inflated. This happens often. I drive old cars and avoid so much hassle.

I only check my tires by looking at them, or occasionally by kicking them, but when I've hit a curb (which has happened more than once), I do watch for the light, in case Ive done damage to the tire.

Re: Cold weather. I have intentionally lowered the pressure in my traction tires to get a better grip on soft snow. It does help! Of course it's necessary to remember to fill them once off the snow!

Besides honing your vehicle performance and safety margins with very little effort, the early warning you get if you pick up a nail during your drive has to improve your survival stats on the road.

You can tell that a tire is low by how the vehicle handles, but by that time, you’ve lost your time advantage to choose how to deal with the problem.

My biggest complaint on these systems is when a single alarm comes up for any of the typical 4 tires on a vehicle. It’s often justification for a higher model level price point.

I find the accuracy of these sensors remarkable, testing them against many and several Costco nitrogen fill stations, at least GM and Subaru equipment, 2007 to 2025 model years. Also check well with our several Sears digital tire gauge/inflator combinations.

I think it gives you an edge if you have them, providing they are a quality installation.

I keep a close watch on my tire air pressure and I feel that a TPS sensor is just a totally useless piece of tech for me, but for some it may be necessary, like the idiot lights on the dash.

I would say you're in the upper few percentiles. Some folks just put a piece of black tape over the Check Engine light.

I'm afraid my wife would freak if she found out her tyre's had air in them to begin with, we don't need to worry her more with an alarm.

...and, I just use the original tyre pressure sensor's, my eyes, to keep a basic eye on them.

For me, TPS system's are just another point of failure that we could all learn to do without, unless you're landing an A380 Airbus of course.

My wife when one of those ‘idiot’ lights come on… it’s like all alarms going off and all hands on deck, battle stations, battle stations….

"just another point of failure" Mine has failed! Checked the tires and they were OK, but the warning light is still on. In my case several other minor things are acting up too--I suspect the car's computer is going bad!

Like many of the under hood add-ons that trigger a "Check Engine" light TPS is added (Maybe even required) to certify vehicle mileage specs. We may not be able to force a driver to keep their tires up to pressure but we aren't allowed to depend on drivers (the majority being idiots) to preserve fleet mileage without prompting.

My Subaru coded on a bad ground or low voltage to a secondary electric fan that I never needed for engine cooling anyway... I never drove it heavy in hot conditions.

Paid $110 twice for a waiver to pass emissions inspection. Emission inspections then went away because the cars that don't self-inspect are a dying breed.

You could say the same about seat belts, Airbags, collapsible steering columns etc.

TPS are a safety device to control the pressure in your tyres and also improve fuel consumption and reduce tyre wear.

A replacement costs around US $ 35 so not exactly a major cost item if one goes down the tubes. My Jeep SRT has just hit 200k and I had only one need replacement.

How many women / young drivers check their tyre pressures ? Here is a report from accident investigations; When you have read it you might understand why TPS exists

In the USA, approximately 1.2 million tire blowouts occur each year, which accounts for about 9% of all vehicle accidents. This translates to an estimated 11,000 tire-related crashes annually, with 400 fatalities attributed to these incidents. Underinflation is a significant factor, contributing to a staggering 300% increase in the risk of a blowout when tires are more than 25% under-inflated.

I have had at least two tyres saved by having the sensors detect flattening tyres before they became beyond repair. Unfortunately in this country there are many failing road surfaces that feel and sound very similar to a flattening tyre. Furthermore there are few places where it is safe to stop to hve a quick look.

Friends,

Growing up, I learned to use a gauge we kept in the glove compartment to check tire pressures daily during long trips and every time we added gas. I don't normally do that now, but have found that by holding the back of my hand to each tire's sidewall when stopped for gas I can quickly tell if a tire is overheating because of low pressure. Of course, I have to allow for differences between front/back and sunlit/shaded.

One day a couple years ago I was at a rally near a large shopping center and was watching the tires of cars as they drove by. At least 1 car in 10 had tire(s) that were obviously low. Since then, I have seen the same ratio.

I typically keep my tires inflated to the high side of the tire's recommendations. This improves gas mileage and gives a larger leeway for pressure losses.

Unfortunately my current modern car has just developed a different tire pressure sensor problem---the device that receives the signals fails when the weather gets cold, so the display shows dashes and the warning light is on.

--JMM

I have a work truck and I regularly drive into a metals recycling depot. I would pick up hitch hikers in my tires and get a flat. I put green slime in my tires and solved the problem nicely, but, killed all my TPMS sensors. They've been deceased now for about 10yrs. The replacements cost about $125 a piece so I don't miss them.

I think the sensors are only useful if someone notices the little icon on the dash any way. My daughter doesn't, and I have to point out her low tires when I see them and hope she stops somewhere long enough to remember to fill them and then fill them.

Jeep have the little Yeööow Icon but also have a massive warning in the middle of the Dash, see foto.
Also where do you get a price from US $ 125 ?? In Germany they only cost about 35 dollars.

Probably my local shop. Charge for removing the wheel and tire and whatever. Doesn't matter because I'm gonna have green goo in the tire regardless. TPMS doesn't prevent flats and green goo does!

What's the term for something that changes so slowly, you can't tell it's changing? I forget.

One time, I just suddenly felt vibrations while driving and found that my left rear tire had gone flat, and it had probably been flat for several kilometers because the tire was almost shredded. If it had been a front tire, I would have felt the steering wheel pulling to one side long before it became flat. Likely, it had begun deflating slowly enough that I didn't notice it as I drove.

After that incident, I bought a handheld tire pressure gauge, and I usually go around the car every morning before driving to work. If tire sensors were available back then, I would probably buy them.

regards,

Vulcan

No, a person familiar with his vehicle can't necessarily tell if a tire is low on air.

I was in field sales in the oil industry. I've driven tens of thousands of miles off road and I've gotten numerous low & flat tires. Yes, you can tell if it's flat, but if pressure drops from, say 36 to 20 PSI, you can't tell. This is especially true on a rear tire. 20 PSI is low enough to let the tire get hot and self-destruct.

Same with a rear tire on the highway at 80 MPH. Of course, this would probably be a function of vehicle weight, suspension design, power steering, etc.

Personally, I balked at the system when it was first introduced, but now I think it's a good idea. It has saved my butt when I was driving through a small town in the middle of the desert. Had I not been alerted to a leak, I would have ended up changing a tire on the side of the road at night. I was able to air the tire up well above normal pressure and make it to my destination where I could service it the next morning.

That said, the vehicle I drive most often has dead batteries in all 4 sensors. I have new sensors, but have not replaced them because the local tire store wants $20 apiece to install them. I'm saving up to buy a tire changing machine. I have over 80 tires on my vehicles and I think it would pay for itself in a year or two. I really think sensors should be required on all FIVE tires.

DING! An idea for another useless idea, or maybe not so useless:

A tire pressure sensor receiver/transmitter that attaches to your shoe. A truck driver that has many tires tires to check could save a lot of time by kicking his tires.

This would give a heads up before even entering the truck so the pressure could be checked before leaving. It could also be added to a smart watch.

The older experienced ones can tell by tapping with a pipe, but that is a dying breed.

I tried an aftermarket TPMS system once. It worked pretty well, except that the sensor was on top of the valve stem. This created a potential leak between the valve stem and sensor so the sensor had to be tight (the sensor constantly pushed down on the valve core). Also, you had to remove the sensor from the stem to inflate a low tire. I tried doing this once and ended up twisting two valve stems to the point of causing them to leak. I ended up making a trip to the tire shop to replace the valve stems and I threw the TPMS system in the trash.

I thought about putting a TPMS system on trailer wheels. It can be hard to sense flat tires on a trailer. One time I got a flat on a trailer in very heavy rain and couldn't feel it, hear it, or see it. It was raining so hard I couldn't see the tire in the rear view mirror. Another driver passed me and waved me over. The tire was completely gone, as was most of the rim!

Most, if not all, the cars spoken about are cars with larger tyres which tend to run at far lower pressures than the strips of rubber on “performance” cars.

It is not easy to tell if a tyre has gone from 50psi to 45, so these sensors are useful in those cars.

Not only that but busier lifestyles mean a lot of people do not do their weekly checks regularly any more. Having a light come on to remind them occasionally is good.

I think the light on my car is designed to come on every two months even if no difference is detected as I do not need to top up pressures most times the tyre warning activates.

Where do you get the idea that "sportscars" have strips of rubber compared to large cars ?? Most sportscars that I am aware of have very broad treadwidth but the sidewalls have a lower profile but the type pressures are the same.

My high performance Jeep Grand Cherokee SRT (500+ HP) has 305.40R20 types with 2.4 bar (34.8 lbs/sq.in.)

My Ford Mondeo Kombi (Fusion Stationwagon in USA) (241HP) has 235.50 R17 tyres and the tyre pressure is identical 2.4 Bar.

My Rover 827 Coupe (169 HP) has the smallest tyres, 205.55R16 tyres and also uses 2.4 bar

So my Jeep tyres are 7cm wider and have a 12.2 cm sidewall height

My Mondeo tyres are 7 cm narrower but have a sidewall height of 11.75 mm Sidewall height so only 0.45cm difference.

And my Oldtimer, the Rover has much narrower tyres but the sidewalls are higher than my Kombi.

So even Tyre sizes differ from 1994 to my 2015 cars, the tyre pressures have remained fairly constant at 2.4 bar

So my performance car has a much wider "strip" but only a slightly lower sidewall height but all 3 use the same tyre pressure.

So no difference between large luxury cars / SuV's and Sportscars.

I can't agree. I've been driving over 60 years, the current one is the first with TPS and I'm impressed. I expected the readings to be there or thereabout, but they're spot on with the forecourt airlines. A couple of weeks back I got a low pressure indication on one tyre, down to 26 psi from about 30. Couldn't tell by looking at it, I blew it up, checked all round for nails etc, and it's been fine since. Without the TPS I wouldn't have known.

About costs, (in UK) we would be told to always get a new valve with new tyres, often by people who weren't qualified to judge. I always thought it was just a ploy to get an extra £ or 2 out of you, and when I was short, at the risk of appearing parsimonious I would decline. After all, the valve body would last the life of the car, and you could change the core if concerned. That's never mentioned with TPS, so saves money.