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If TPMS is tire pressure, then you are being unfair. There are cars like Toyota and Audi that have sensors that don't work well and even frequent service can't keep them off (to the point where some will not-quite-suggest disabling them).

So if you are going to downgrade for that, at least have a look at the tires directly and see if one is obviously lower than the others.

If the driver has snow tires, they're a safer driver than one with all-weather and a blank dash.

You can get TPMS on a second set of wheels. I have them on my snow tires and they were like $80.

For mine, I had to pay for a TPMS reset every tire change. This isn't worth it.

TPMS reset is usually holding a button and typically in your driver's manual for the vehicle. Found this out myself when my tires got replaced and they couldn't reset my TPMS sensors.

I have a tool to reset them myself, I think it was free from Tire Rack when I bought the tires. It's like a keyfob and pretty simple to use, you just hold down a button.

It would be worth looking into getting.

I always swap my own tires in the summer/winter because it takes me less time to do it than to drive to the shop. TPMS, but it can be such a pain.

My previous car, 2010 VW I could switch from summer to winter wheels/tires and drive away. TPMS would figure it out just fine. Now I have a Subaru and am debating buying a $100 tool to reset them. It won't take long to pay for itself, but as it is now, the light is still on.

Worse, my Ram has positional sensors and I haven't seen any "cheap" tools. It happens to be the same set of wheels, but I rotated them and it expects different pressure in the front vs rear. The light is on and it yells at every start because the rear tires are underinflated. How hard can it be for a car to learn which tire is on which corner of the vehicle?

In California, summer tires get the best traction and all-seasons are generally worse (many people mistakenly believe that all-seasons perform better than summer in the rain, I suppose because winter is the rainy season here).

I guess it depends on what part of California you're talking about but all-seasons will generally outperform equivalent grade summer tires in the rain if temperatures start falling below 50-55° or so. A summer tire's grip falls off precipitously [1] when temperatures reach 40-45° but the loss of grip in that "NorCal winter" kind of weather can reduce their performance below that of all seasons. Just because they haven't lost a dangerous amount of grip doesn't mean they haven't fallen behind the grip available to a tire with a more temperature insensitive compound.

[1]: https://m.tirerack.com/tires/tiretech/techpage.jsp?techid=27...

Agreed, I should have specified that all-seasons are the safe option in some parts of California. My frame of reference is the warm climates of Silicon Valley and SoCal. Summer tires could even lose traction in one of the colder nights in a San Jose winter.

I'm betraying my ignorance but I thought SV/SF were relatively temperate climates. Nothing like Seattle, but still 50 low to 75 high most of the time?

in theory, the difference between summers and all-seasons is the rubber compound used. all things being equal, the summer compound will perform better when it's hot outside. in reality, most people in the US just don't care and run all-seasons year round. people tend to only buy summer tires for performance-oriented vehicles, so the tires offered with summer compound tend to be aggressive tires with less tread. if you pick a summer tire at random, it may well be less capable than an all-season tire in the rain. the superior compound can't grip if it can't evacuate enough water from the contact patch.

FYI, there is a difference between all-weather and all-season tires.

https://info.kaltire.com/all-weather-vs-all-season-vs-winter...

Tire pressure sensors are super flaky. Mine come on randomly all the time, and after the first few dozen times I stopped to put a real gauge on them and saw that all four were right at the rated pressure, I've gotten to the point where I just ignore it and punch the button on the dash to hide the warning. It's the kind of false negative feedback that is especially unhelpful.

It doesn't help that it is completely opaque what the thresholds are for when the warning light goes off; I also don't know whether one is supposed to recalibrate anything if you change the type of tire that you are running - for instance, I run snow tires during the winter that have a different PSI rating than my all-seasons the rest of the year...

You car manufacturer should be setting the psi, rather than the tire manufacturer. There are indeed manufacturers who recommend higher pressure on winter tires for that car model, but it's still the model and not the tire that drives it. (Tires have a max inflation pressure, but the recommended pressure comes off the door jamb of your car.)

Or behind the fuel door (Volkswagen; took me months to find it).

I now have a Civic which just has a generic "tire pressure low" warning, but on my previous car, a Dodge Dart, it told me the pressure for each tire.

TPMS is also relatively easy to reset (just read the manual) it does not require professional service. You usually do need to do it seasonally due to fluctuations in outside temp. Drivers should really be aware of it.

I'd encourage you not to rate low over the TPMS sensor light - it's far from a guarantee of actually low tire pressure.

On many cars, TPMS sensor problems cause the light to blink at startup, then stay on steadily just like you had a low tire. That includes "the tire doesn't have a sensor", which can save about $200 on each valve stem. Given how quickly an Uber driver can rack up mileage, I wouldn't be surprised if many of them are just saving money on tires by getting sensor-less ones.

(Admittedly you can't tell if they're checking the pressure manually; I would think so to save on tire lifespan, but it's obviously not guaranteed. Of course, not seeing the light isn't a guarantee either.)

Tires are just pieces of rubber. The sensor is attached to the wheel and stays in place after tires get changed.

If you buy a set of wheels dedicated to winter tires, then you can swap between summer and winter in thirty minutes at home.

Otherwise, you need to put your dirty tires in the back seat, drive to a shop, pay $100 and wait for an hour or two to get them swapped and balanced.

Yep, that. I guess TPMS for the winter rims would be a one-time cost that should outlast the tires, but it's still pretty common to not get it. An extra ~$800 up front, last time I had a tire replaced the sensor ended up damaged anyway, and if your winter tire pressure is different it'll just complain uselessly anyway.

Plus, if you're already spending >$1000 for winter tires/wheels, it's hard to justify TPMS on top of that.

And if you're paying that much for the added safety/performance, you're not the kind of person who needs TPMS to nag them into inflating to the proper pressure.

If you're spending >$1000 on tires, how is a $80 set of TPMS hard to justify?

Presumably you're buying snow tires for safety reasons. Proper tire pressure is important for traction, thus safety. And winter is the time when tire pressure fluctuates the most.

> And winter is the time when tire pressure fluctuates the most

genuinely curious, why? I thought tire pressure fluctuations were linearly related to air temperature fluctuations. does the temperature vary more in the winter than in the summer?

At least in some of the US, quite a bit more. Winter might be swings of >50F, especially night to day, while summer variation is likely to be <40F. I'm not what all weather patterns factor into that, but a major part is that winter air is dryer, and water vapor does a lot to 'buffer' brief temperature changes.

That said, I mostly end up checking my tires more in the winter because I care more; if a tire is only a few pounds low I'd still prefer to handle it before I have to go drive on snow during a cold snap.

Sure, but if you’re the kind of person who buys winter tires (which IME is pretty rare in the widwest USA), you probably know that and check your pressure every couple weeks. And it probably only fluctuates a couple PSI which is well within safe bounds.

Sensors are frequently and unavoidably damaged during unmounting. Many shops just replace the sensors as a matter of course when replacing the tire, since there is no way to test the sensor until the new tire is mounted and inflated.

> which can save about $200 on each valve stem.

What kind of car requires $200 TPMS sensors? Most are in the $35-$55 range, even on very high end cars.

Hell, even my dealership "only" charges $80 per wheel. Though we quickly learned the local tire shop does them for $40 a pop with a much quicker service. I generally just let the dealer service our car since there's not many mechanics in the area qualified to service hybrids anyway, but hell if I'm letting them rip us off on anything related to the tires again (even though their prices for Toyota factory tires are quite fair, I'm not paying an extra $40 a tire for the sensors when we buy a new set).

my favorite was the TPMS on my spare was alerting, unfortunately my car while it had TPMS did not state which wheel it was on.

TPMS modules are insanely flaky. That light will pop for reasons ranging from synchronization issues to using a spare without a module (not the donut!)..none of which impact safety at all.

Same with "check engine." My last car had the check engine light on from years 3 to 15, when I sold it. The reason was a faulty sensor but the actual mechanics were sound and not worth fixing.

I'm amused that you think you're holding drivers to professional standards. Professionals know when to ignore the dummy lights intended for the masses...

...which is not to say you should change anything, because Uber drivers ARE the masses, so it makes little sense to treat them like professionals!

Uber simply organized hitchhiking.

> My last car had the check engine light on from years 3 to 15, when I sold it. The reason was a faulty sensor but the actual mechanics were sound

Some Nissan models used to have a fun version of this where the check engine light came on to notify you about a problem with... the check engine light. It was a bug, obviously, but not a sensor wrongly detecting a fault. Rather, the car's only way of saying "if something goes wrong the check engine light might not activate" was to activate the check engine light.

Whatever the underlying issue, I assume software, replacing sensors didn't work and resetting the light would only last for a few hundred miles. It was effectively impossible to keep the light working, so the mechanic-recommended fix was to just disable it.

> so the mechanic-recommended fix was to just disable it.

Which can make it impossible to pass state emissions/safety testing, because they expect to see all the lights turn on at power-up.

The trick is to rewire the light to some other light instead ;)

Hitchhiking and realtime carpooling is not the same experience. Former is random car, random passenger; latter is known car, random passenger.

Not really. I don't have the ability to choose which car I ride in with Uberpool. I have limited ability to choose what car I ride in when I carpool the normal way via Bay Area casual carpool stops (I can refuse to get in the next car in line, and that's about it). And, in either of those scenarios, the most important factor (the driver) is essentially random as well.

Please see my edit regarding known deaths resulting from improperly inflated tires.

> That light will pop for reasons ranging from synchronization issues

Yes that exactly correct. It's based on an engineering principle called fail-safe:

https://en.wikipedia.org/wiki/Fail-safe

When the light is on, you have no assurance that the tires are properly inflated. Period. If the TPMS light is off, you can be well-assured that tires are inflated properly.

Yes, the system is finicky (by design). Yes the system can be costly to maintain (I do it myself it's it expensive and time-consuming). These are the responsibilities one must take on if they wish to be transporting the public.

>When the light is on, you have no assurance that the tires are properly inflated

I mean, you could always, you know, check. With a tire pressure gauge. Like on every car ever that didn't have this TP thingy. Honestly, you don't even need to do that - if the tire is low enough to be a safety risk, it will be visibly flat.

Would you down-rate an Uber just for not having this sensor at all?

TPMS is a US requirement. I drive a Canadian car that detects if the tire speeds have gone out of sync and reports if there’s an anomaly.

Doesn’t always work for gradual pressure loss, and doesn’t tell me which tire, but that’s what the gauge is for.

My Jaguar will throw a Check Engine for Fuel Cap Insufficiently Tightened.

any vehicle with an evap system will. it's an emissions thing

The rubber on the cap eventually cracks as well. I wonder if Vaseline or something would make it young again.

That can't be a very expensive part to replace. May as well do it.

I agree. Worth a try. Worst case scenario, I’m out $15.

I'd suggest adding #4. Not using turn signals. This makes things slightly less safe for everyone else on the road (including peds + bikers) and it costs the driver nothing to properly signal.

Well in some places, you will be rating %95 of drivers below 5 stars then, since nobody uses turn signals in those cities.

Well then 95% of the drivers in some cities are terrible and deserve it.

I highly doubt that 95% claim though.

Come to most large cities in america!

I live in Manhattan, and signaling compliance is way higher than 5%.

California then?

Mechanical failure is a fart in a hurricane compared to human factors when it comes to safety. I'm not gonna ding anyone for being too cheap to put TPMS sensors in their snow tire rims. I'm not gonna ding anyone for a CEL either. 95% of the time it's basically just complaining that an emissions system is not in an optimal state. In a work vehicle setting you do not fix this when it happens. You plan a time in the future to take the vehicle down for maintenance, just like patching a prod system.

In a non-work vehicle, I imagine most people do the same. My wife's car has the MIL/CEL lit for the last 6 weeks for a failed knock sensor. I ordered the part and will probably change it this weekend, but we're not parking it and it's not a safety or even an emissions concern.

The CEL being on isn't enough for me to ding a driver but I've also never received an Uber ride where the CEL was on but the car was in otherwise top condition. There is definitely enough of a correlation between a CEL being on and the car having a blown suspension (bushings, struts, CV joints), some engine belt or accessory with a bearing about to fail, or brake pads so worn it's basically riding on nothing but the wear indicators (squealers). Sometimes I even get lucky and get all three.

Maybe it's reasonable to report the CEL in that situation since it's something most riders will notice and can easily be verified by Uber with a photo unlike the condition of the mechanical bits themselves.

"TPMS sensor light is on (major safety risk)"

It really isn't. (very) low tire pressure is a major safety risk. The TPMS sensors I've had all seem to go off at minor deviations (few psi) from the tire pressure; deviations that aren't a safety risk.

A useful reminder that the winter is coming, but hardly a major safety risk.

Close to 300 people died [1] in the 90s due to improperly inflated tires. Sorry, but I don't screw around with safety factors like this when I'm being hurled down freeway interchanges at 70 mph.

> The TPMS sensors I've had all seem to go off at minor deviations

Good (IMHO)

[1] https://en.wikipedia.org/wiki/Firestone_and_Ford_tire_contro...

300 deaths seems like a very insignificant figure to be worked up over.

Seriously. Ten times that number die in traffic accidents in the US daily.

If that's your level of risk sensitivity, don't get in a car.

What? About 100 people die from road vehicles per day in the US, not 3000.

Ah sorry, that's the global statistic, not the US statistic.

Still, both statistics illustrate the point - 300 deaths a few decades ago involving faulty tires that may have been exacerbated by manufacturer-recommended underinflation have basically 0 bearing on the marginal risk of driving with a TPMS warning light illuminated.

Uh no, according to your own source they died because of tread separation caused by a number of factors, one of which may have been underinflation. But in this example the 'underinflated' value was manufacturer recommended, so a TPMS wouldn't have helped anyways.

It isn’t like these doors tensions are standardized. How much pressure to apply to the trunk door of this car you’ve never ridden in before? No idea, it might even be the auto closing kind. Thankfully, most Ubers are priuses, but not always.

That's why you should push doors/trunks/hatches closed and not throw/shove/fling them. I don't mean "push", as in close it like your closing the front door after sneaking home after curfew in high school. I mean it more like keep your hand on the door and slowly accelerate until you've given it enough momentum.

You aren’t pushing so much as pulling. It is much more difficult to control from the inside. Anyways, I just don’t ride in enough cars to get used to the different tensions (maybe if I took Uber more). Also, it always seems to be the American sedans that have the most problems, which we don’t have too many of on the west coast.

I can understand that. Honestly, my experience with modern midsize sedans (Altima in particular, Accord, Camry, Sonata, etc) is that the manufacturers view the rear doors as throwaway areas for "engineering" weight out of the car. The rear doors on these cars honestly weigh about half what the fronts weigh and they fly open and close as if made of paper maché.

> TPMS sensor light is on (major safety risk)

Not necessarily, it could be that the sensor is either defective or missing, which doesn't mean the tire pressure is wrong.

Exactly. The light being on means "You don't know" if your tires are safe. Light off, means "You positively know your tires are safe".

Read about:

https://en.wikipedia.org/wiki/Fail-safe

Or you positively know rhat the light has been physically disabled, which is trivial on most cars.

Regardless, it seems an incredibly insensitive thing to give a poor rating over.

Or the car doesn't have TPMS... Like any car I have ever owned...

These TPMS sensors do add a significant price increase on the tires, which most people I know about choose to avoid at the expense of this "lights on".

We do have to swap our tires for winter tires up north, so I'm not getting tires with the sensors.

I googled "Firestone Ford" before reading to the end of the sentence and seeing your link, and amazingly, the first result is a woman named "Martha Firestone Ford" [1], whose name comes from the same business relationship that produced the debacle.

[1] https://en.wikipedia.org/wiki/Martha_Firestone_Ford#Family