Tire pressure sensors and new tires question.

[GH85Carrera]

In 29 years of owning my 85 911 I have never had to replace the tire pressure sensors. I check the pressure the old analog way. Never a water bump, power steering pump, no ABS problems and never once a check engine light!

Anyway, my wife's 2017 Macan is all the way up to 27,000 miles and the tires need to be replaced. There is a little more wear, but with summer approaching it is time for new tires. The factory delivered Pirelli tires are very noisy now and old.

Is it customary to leave a working system alone, or replace the sensors? Can just the battery in the sensors be replaced or is it the entire sensor? How long do they last?

If they have a 10 year life, it makes sense to me to replace them now. Should we use Porsche OEM sensors or aftermarket ones. The pressure monitoring system has worked well and it did let us know one tire was low when she picked up a nail. It was patched and still in place.

I have zero knowledge of the typical tire pressure monitors on modern vehicles that the US government has mandated all cars have. I have heard horror stories from others on various vehicles.

So I need some Pelican brain trust wisdom please.

[David]

I've never had a Porsche tire pressure sensor go bad and I've had 10 years and over 100k miles on them.

[masraum]

Originally Posted by GH85Carrera

In 29 years of owning my 85 911 I have never had to replace the tire pressure sensors. I check the pressure the old analog way. Never a water bump, power steering pump, no ABS problems and never once a check engine light!

Anyway, my wife's 2017 Macan is all the way up to 27,000 miles and the tires need to be replaced. There is a little more wear, but with summer approaching it is time for new tires. The factory delivered Pirelli tires are very noisy now and old.

Is it customary to leave a working system alone, or replace the sensors? Can just the battery in the sensors be replaced or is it the entire sensor? How long do they last?

If they have a 10 year life, it makes sense to me to replace them now. Should we use Porsche OEM sensors or aftermarket ones. The pressure monitoring system has worked well and it did let us know one tire was low when she picked up a nail. It was patched and still in place.

I have zero knowledge of the typical tire pressure monitors on modern vehicles that the US government has mandated all cars have. I have heard horror stories from others on various vehicles.

So I need some Pelican brain trust wisdom please.

You are a "replace it before it fails" kind of guy.

Originally Posted by David

I've never had a Porsche tire pressure sensor go bad and I've had 10 years and over 100k miles on them.

I think that pretty closely mirrors my experience.

I bought my '08 boxster in 2014 with ~21k miles on it. I would assume at 6yo with barely over 20k miles, it probably had the original TPMS in the 4 wheels. It's now 10 years later, and I don't remember anyone ever changing them out.

[rockfan4]

The sensors you have are likely not Porsche branded, but are the same used in VW and Audi cars that use sensors.

Batteries are not replaceable, you have to replace the whole sensor.

The wife drives a GM product with similar sensors. It is a 2016, but has 114,xxx miles on it. We bought it 6 years ago, and it is unlikely the sensors were changed before we bought it. We have now changed tires twice, and two of the sensors have died. Part of me says I should replace them. Part of me says there's a tire pressure gauge in the center console. It's all up to whether you can tolerate that light. The sensors go into a very low power mode when you aren't driving, yours may be good for several years yet. If you have the ability to break the bead on the tire and get in there and replace the sensor yourself, I'd say wait. If not, and you think the next set of tires is going to last you more than 4 years, and your wife doesn't want to see the light, get them changed now.

My problem is the wife sees all the lights on the dash with the same criticality, and if I tell her to ignore the TPMS light, she'll ignore the oil pressure light and everything else on the dash. I'll get in the car and ask her about something, and it's always "oh, that just came on".

[TimT]

A decent Tire shop should have a scan tool to check the battery level in the sensors..

Chances are the 7 y/o old sensors are nearing end of life

[GH85Carrera]

My wife grew up with a dad that actually taught her about cars. She listens to funny noises and pays attention to the gauges. She would never tolerate a light on the pressure monitors, or any other warning light. She has me go check them when the sensors read one is to far out of range. Often it is a pound or two low, or more in the cold winter days.

I was just hoping for an estimate on how long they last. If they go another 7 or 8 years that will be fine. I just don't see the logic of trying to get two more years out before they die and have to pay for tire dismounting and then replace the sensors.

[rfuerst911sc]

My wife's 2010 Volvo XC90 original sensors made it 13 years before they triggered a dash warning . We needed tires this year so had local tire shop replace tires and sensors . The sensors were generic and paired easily . The sensors were $75.00 each . I agree have a tire shop scan your sensors and go from there .

[GH85Carrera]

I just looked up the price for the sensors. Wow, Pelican wants just under $150 and I have seen some place that want $170 or more. We may well go with the "if it ain't broke, don't fix it" mode.

I had no idea the sensors were gonna cost $600 or more for a set of 4.

[p911dad]

I had the sensors fail years ago in both our 2008 4Runner and our 2008 Malibu. I found hacks to disable both systems after I found out how much it cost to replace them. Of course years have gone by and now I have no idea where I found them online.

[Zeke]

Under 20 bucks for all 4 on AliExpress for the Audi ones. Now if you enter "porsche" the price jumps to $187 ea. +shipping. You might do some research on this.

I use AliExpress coil packs on the Jag and they work fine. Looking at a Bosch and a knockoff and I can't tell the difference from the outside. I've had them on there for maybe 7 years.

[kochtools]

TPMS sensors are designed for an average 10-year life ... actual life will depend on use-case, including climate.

Denso (reputable) sensors from Rock auto are $50 ea

Based on the current driving style, they will fail prior to the next tire change, so do it now ... avoid the grief and potential damage associated with a replacement that is not coincident with a tire change.

Honestly ... I do not get the language around old cars without such things being better. Advance notice of leaks is valuable information ... for safety and for maximizing the life of the tire. When you move to low-profile tires, the "eyeball test" is no longer valid until the tire is damaged beyond repair.

[wdfifteen]

Originally Posted by TimT

A decent Tire shop should have a scan tool to check the battery level in the sensors..

Chances are the 7 y/o old sensors are nearing end of life

One sensor in my Tundra lasted 7 years. It cost $60 to replace it. The tech said the scan showed another battery was low but I chose to wait to change it until I need new tires. If the light starts coming on I’m going with a strategically place piece of electrical tape on the dash and a a tire pressure gauge in the console.

[TimT]

https://www.tpms.com/Porsche-Macan-Huf-Intellisens-RDE018-TPMS-p/uvc0018pcarset-macan.htm

https://www.tpms.com/Porsche-OEM-Huf-TPMS-Sensor-9A790727502-433MHz-p/h0047-porsche.htm

[wildthing]

My Sienna's TPMS sensors went bad after 11 years. When I changed wheels on my used 991 I decided to replace the sensors because I have no record of them being replaced, even though the scan tool yielded no problems yet according to my mechanic. But since the wheels are new, might as well...

[Steve Carlton]

Why not replace one at a time as they go. Live on the Wild Side.

[WPOZZZ]

Originally Posted by GH85Carrera

I just looked up the price for the sensors. Wow, Pelican wants just under $150 and I have seen some place that want $170 or more. We may well go with the "if it ain't broke, don't fix it" mode.

I had no idea the sensors were gonna cost $600 or more for a set of 4.

I've used ITM sensors for my 987 and BMWs. About $100 for a set.

[jhynesrockmtn]

My wife's 2015 Macan still has the original sensors working fine in her summer tires. I bought a winter set a few years ago. Aftermarket sensors on Porsche wheels. They sync'd up to the system fine and work well. I'm not sure of the brand but given where I bought them from, I'm guessing not Porsche :-)

[blucille]

as others have said, I've got TPMS sensors that have been running 10+ years on a variety of cars, no issues yet.

I put a set of winter wheels on my Cayman, they had the wrong version of TPMS sensors, so a tire shop swapped them for me, without fully dismounting the tires, it was a piece of cake. These sensors (4 pack for $120) have been working great.

Autel MaxiTPMS 315MHz/433MHz 2 in 1

https://www.amazon.com/gp/product/B094VJNWXD/

[GH85Carrera]

Originally Posted by blucille

as others have said, I've got TPMS sensors that have been running 10+ years on a variety of cars, no issues yet.

I put a set of winter wheels on my Cayman, they had the wrong version of TPMS sensors, so a tire shop swapped them for me, without fully dismounting the tires, it was a piece of cake. These sensors (4 pack for $120) have been working great.

Autel MaxiTPMS 315MHz/433MHz 2 in 1

https://www.amazon.com/gp/product/B094VJNWXD/

Thanks. I will pass this on the my wife. It will be her choice to replace or not. She has been getting a new car every 10 years or so. She loves her Macan, and it is pristine. With the face that new Macans are all electric, she may well keep it longer than 10 years. I suspect the Ice Macan may go up in value with only new electric versions sold new.

[blucille]

Originally Posted by GH85Carrera

Thanks. I will pass this on the my wife. It will be her choice to replace or not. She has been getting a new car every 10 years or so. She loves her Macan, and it is pristine. With the face that new Macans are all electric, she may well keep it longer than 10 years. I suspect the Ice Macan may go up in value with only new electric versions sold new.

Same boat, my wife loves her Macan GTS, still on its original TPMS, and winter wheels, the same. She wants to drive it forever, which I know--for her--means up until 80 or 100k....so another 6 years at this rate. If we can wait until our son is out of college, I'd be excited and impressed.

my theory is, if you are swapping tires and the TPMS are showing they are down to 30% or less battery life, swap them when you get new tires. order the Autel units, and you'll be good. Tire shops LOVE to mark up the TPMS sensors significantly.

You do know, your 85 has none of this nonsense....although I added them to my '79 just for fun.