Change TPM warning values?
07-09-2018, 12:16 AM
#1
Burning Brakes
Thread Starter
Change TPM warning values?
I get a lot of TPM warnings because I don't have 47lbs of pressure in my left rear tire. I don't like to run that much pressure. I run 44lbs in the rear and 40lbs in the front. So, I have to fill the left rear to 47lbs, drive it a little while, then let some air out. Then TPM is happy for a few weeks.
07-09-2018, 11:32 AM
#4
Rennlist Member
Isn't 47psi absurdly high? In fact, I thought most people kept their tires in the mid-30s. Mine are something like 34/38 and I don't get lights unless a tire falls too far outside those parameters, but I think I "trained" the computer to those values. Besides the winter tire option make sure you also have it set to partial load.
07-09-2018, 12:16 PM
#5
For freeway commute I run 42 rear and 37 front when cold (compensated for ambient). This keeps the tires rolling on the center of the tread. I get tremendous mileage on a set (25K miles plus on the rears and 35 to 40K on the fronts ... MPSS).
At one time I was diligent about releasing air before spirited driving but then I got lazy. My pressures could get to 50 / 44 psi on some drives.
At this pressure the car bounces and you need to set up for turns as though you were piloting a dirt bike. I had actually let myself get used to that but it did make driving a challenge.
On a recent trip a friend rightly gave me some **** and I lowered to 37 and 33 cold. All I will say is ... WHAT A DIFFERENCE!!!
And Thank You to the friend 8)
Sincerely ... an idiot for getting lazy.
At one time I was diligent about releasing air before spirited driving but then I got lazy. My pressures could get to 50 / 44 psi on some drives.
At this pressure the car bounces and you need to set up for turns as though you were piloting a dirt bike. I had actually let myself get used to that but it did make driving a challenge.
On a recent trip a friend rightly gave me some **** and I lowered to 37 and 33 cold. All I will say is ... WHAT A DIFFERENCE!!!
And Thank You to the friend 8)
Sincerely ... an idiot for getting lazy.
07-09-2018, 12:17 PM
#6
PS: I don't get any TPMS warnings changing the pressures between drives.
07-09-2018, 04:05 PM
#7
Just reset mine to 34/39. Retrain TPMS with “new” values. Use Durametric to kill the tire warning lamp on display. Drive.
Trending Topics
07-09-2018, 04:21 PM
#8
I like to run mine at 33/37 when they are hot, but to achieve that, cold tires are low enough that the TPMS sounds the alarm. Hate it but I'm not sure I want to kill the warning lamp.
08-23-2018, 06:14 PM
#9
I am still wrangling with the TPMS. System info is 3# less that what I know to be true. So, cold tires produce a warning light. Worse, last weekend it said I had a flat tire. Pulled over and it was a perfect (for what I want) 33 front, 37 rear with hot tires.
I came across this, a guy who was dealing with the same problem on an 08 Caymen:
Innacurate TPM
https://www.planet-9.com/987-cayman-...-systems.htmlS Systems
10/2/2010
While some of you report accurate pressure readings on your TPMS systems I am one of the unlucky ones whose 2008 Cayman system is defective. The actual pressure readout is consistently 3-4 psi lower than shown with a calibrated manual gauge. Worse, during hot weather it frequently signals a false -4 psi alarm for one tire when the tire has lost no air at all is at factory spec, and is the same as the other tire on the same axle which signals no warning. Porsche’s solution is to overinflate all tires to reset the warning system.
The first time I called the dealer about the problem in 2009 I was told I needed to try “tricking” the system to avoid false alerts. The service writer said other owners had the same complaint and tried using a winter tire setting to fool the computer. He thought Cayman air pressure was supposed to be 35 front and 42 rear and was surprised when I said my door plate says 30 front and 37 rear. I later learned from his mechanic that the dealer had been overinflating several customer cars to shut off false alarms.
On the first dealer visit the mechanic and I cross-checked our manual gauges. My calibrated gauge and his certified gauge were within a half pound of each other and confirmed my TPMS’s low readout. He reset the system but the false warning soon reappeared.
On the second visit the dealer, under the supervision of the field rep, replaced all four sensors. No change.
On the third visit they kept the car for a week while they exchanged emails with Zuffenhausen. They replaced the RDK control unit. (RDK—Reifendruckkontrollsystem—German for TPM.) No change: The dash “actual” tire pressures still read 3-4 psi low. And the next time it got hot the TPMS signaled a false alarm. (When ambient temperature goes up so does tire pressure supposedly lessening the chance for a false alarm. A true alarm should sound when pressure goes down not up!)
The next summer (2010) I took the car to the dealer with the same symptoms—alarm on with a false -4 psi drop and same inaccurate pressure readouts. But this time the dealer and customer rep in Atlanta pronounced the system in good working order. They blamed me for using a manual gauge and factory pressure settings instead of the tell-tale readout. The mechanic, service manager, field rep and customer commitment specialists all told me I must not use a manual gauge to set adjust tire pressure but rely only on the dash “add air” readout (but not to use the actual pressure dash readout) and go through a process they call “zeroing”.
Here’s how zeroing works for those of you who haven’t heard it from your dealer:
• The low pressure warning signals an audible and visual alert. (A tire cross-section symbol with an exclamation point.)
• The dash “add air” warning shows a low tire. (For example, LF -4psi.)
• Ignore the readout that shows the “actual” pressure in each tire. (For example LF +32)
• With the ignition on and the ”add air” menu displayed, you add 4 psi to the LF even though a hand gauge shows it at factory specs and the same as the RF.
• Then, in my case, after adding air to the LF the display changes and shows the other three tires low.
• Zeroing involves going back and forth adding air to the other tires and checking the readout until all tires show --(zero).
The pressures end up 3-5 psi higher than the factory specifications on the door post plate and owner’s manual. I was told to ignore those recommendations. But the alarm goes off.
When I protested to the customer commitment specialist, saying my owner’s manual said to always use a manual gauge and did not describe the zeroing process, he emailed back: “To my knowledge our owner’s manual does not mention the use of a hand gauge.”
The factory rep was wrong. My manual says:
• p. 217: “Always use an accurate tire pressure gage when checking inflation pressures.” P. 217
• P. 234: “Checking tire pressure with a pressure gage 1. Remove the valve stem cap from the tire. 2. Press the pressure gage onto the valve stem. Note on operation: Do not press too hard or force the valve stem sideways, or air will escape. If the sound of air escaping from the tire is heard, reposition the pressure gage. 3. Read the tire pressure on the gage stem and compare it to the permissible tire pressure. This information can be found on the tire pressure plate or in the (owner’s manual) chapter Technical Data. P. 234
So the manual in print says use a manual gauge and go by the Porsche specs. Verbally, however, all of the Porsche reps up the chain of command all the way to Germany say don’t use the manual gauge and do not go by the owner’s manual settings.
When that advice is followed the tire pressures end up higher than required (unless you’re a lucky owner with an accurate system), resulting in a harsher ride, possible faster wear in the tread center and possibly longer braking distances. Worse, though, the TPMS system is no longer a backup because it is now dictating tire pressure specifications. If it gets even further out of whack the tire pressures could stray even further from factory owner’s manual specs.
Where TPMS has been mandatory in the United States since 2007, it has remained an option in Germany until next year. Even so Porsche owners’ forums in Germany, where I have done a lot of consulting, are chock full of complaints about their optional systems malfunctioning. An example: “Porsche RDK ganz großer Mist ... immer Fehler und das ständige gepiepse nervt. Taucht meistens auf, wenn Sie die außentemp ordentlich verändert. Das Porsche RDK ist zu fein abgestimmt und zeigt schon Veränderungen ab 0.1 Bar.“ What he says, essentially, that Porsche’s TPMS system is ****; that the continual false alarms are unnerving, and that Porsche’s system is too sensitive.
Porsche needs to quit misleading its customers and find a fix for those owners whose systems don’t’ work properly. And Planet 9 ought to consider correcting its link that say TPMS “communicates the exact pressure of each tire and/or their deviation from ideal pressure” and that it “does away with the need for regular air pressure checks at the servicestation, which often prove highly inconvenient.” Given the problems some have had, Porsche owners might consider heeding the advice of the National Highway Traffic SafetyAdministration which created the TPMS law and check tire pressure at least once a month using a manual gauge and factory specs and only rely on TPMS as a safety backup.
I came across this, a guy who was dealing with the same problem on an 08 Caymen:
Innacurate TPM
https://www.planet-9.com/987-cayman-...-systems.htmlS Systems
10/2/2010
While some of you report accurate pressure readings on your TPMS systems I am one of the unlucky ones whose 2008 Cayman system is defective. The actual pressure readout is consistently 3-4 psi lower than shown with a calibrated manual gauge. Worse, during hot weather it frequently signals a false -4 psi alarm for one tire when the tire has lost no air at all is at factory spec, and is the same as the other tire on the same axle which signals no warning. Porsche’s solution is to overinflate all tires to reset the warning system.
The first time I called the dealer about the problem in 2009 I was told I needed to try “tricking” the system to avoid false alerts. The service writer said other owners had the same complaint and tried using a winter tire setting to fool the computer. He thought Cayman air pressure was supposed to be 35 front and 42 rear and was surprised when I said my door plate says 30 front and 37 rear. I later learned from his mechanic that the dealer had been overinflating several customer cars to shut off false alarms.
On the first dealer visit the mechanic and I cross-checked our manual gauges. My calibrated gauge and his certified gauge were within a half pound of each other and confirmed my TPMS’s low readout. He reset the system but the false warning soon reappeared.
On the second visit the dealer, under the supervision of the field rep, replaced all four sensors. No change.
On the third visit they kept the car for a week while they exchanged emails with Zuffenhausen. They replaced the RDK control unit. (RDK—Reifendruckkontrollsystem—German for TPM.) No change: The dash “actual” tire pressures still read 3-4 psi low. And the next time it got hot the TPMS signaled a false alarm. (When ambient temperature goes up so does tire pressure supposedly lessening the chance for a false alarm. A true alarm should sound when pressure goes down not up!)
The next summer (2010) I took the car to the dealer with the same symptoms—alarm on with a false -4 psi drop and same inaccurate pressure readouts. But this time the dealer and customer rep in Atlanta pronounced the system in good working order. They blamed me for using a manual gauge and factory pressure settings instead of the tell-tale readout. The mechanic, service manager, field rep and customer commitment specialists all told me I must not use a manual gauge to set adjust tire pressure but rely only on the dash “add air” readout (but not to use the actual pressure dash readout) and go through a process they call “zeroing”.
Here’s how zeroing works for those of you who haven’t heard it from your dealer:
• The low pressure warning signals an audible and visual alert. (A tire cross-section symbol with an exclamation point.)
• The dash “add air” warning shows a low tire. (For example, LF -4psi.)
• Ignore the readout that shows the “actual” pressure in each tire. (For example LF +32)
• With the ignition on and the ”add air” menu displayed, you add 4 psi to the LF even though a hand gauge shows it at factory specs and the same as the RF.
• Then, in my case, after adding air to the LF the display changes and shows the other three tires low.
• Zeroing involves going back and forth adding air to the other tires and checking the readout until all tires show --(zero).
The pressures end up 3-5 psi higher than the factory specifications on the door post plate and owner’s manual. I was told to ignore those recommendations. But the alarm goes off.
When I protested to the customer commitment specialist, saying my owner’s manual said to always use a manual gauge and did not describe the zeroing process, he emailed back: “To my knowledge our owner’s manual does not mention the use of a hand gauge.”
The factory rep was wrong. My manual says:
• p. 217: “Always use an accurate tire pressure gage when checking inflation pressures.” P. 217
• P. 234: “Checking tire pressure with a pressure gage 1. Remove the valve stem cap from the tire. 2. Press the pressure gage onto the valve stem. Note on operation: Do not press too hard or force the valve stem sideways, or air will escape. If the sound of air escaping from the tire is heard, reposition the pressure gage. 3. Read the tire pressure on the gage stem and compare it to the permissible tire pressure. This information can be found on the tire pressure plate or in the (owner’s manual) chapter Technical Data. P. 234
So the manual in print says use a manual gauge and go by the Porsche specs. Verbally, however, all of the Porsche reps up the chain of command all the way to Germany say don’t use the manual gauge and do not go by the owner’s manual settings.
When that advice is followed the tire pressures end up higher than required (unless you’re a lucky owner with an accurate system), resulting in a harsher ride, possible faster wear in the tread center and possibly longer braking distances. Worse, though, the TPMS system is no longer a backup because it is now dictating tire pressure specifications. If it gets even further out of whack the tire pressures could stray even further from factory owner’s manual specs.
Where TPMS has been mandatory in the United States since 2007, it has remained an option in Germany until next year. Even so Porsche owners’ forums in Germany, where I have done a lot of consulting, are chock full of complaints about their optional systems malfunctioning. An example: “Porsche RDK ganz großer Mist ... immer Fehler und das ständige gepiepse nervt. Taucht meistens auf, wenn Sie die außentemp ordentlich verändert. Das Porsche RDK ist zu fein abgestimmt und zeigt schon Veränderungen ab 0.1 Bar.“ What he says, essentially, that Porsche’s TPMS system is ****; that the continual false alarms are unnerving, and that Porsche’s system is too sensitive.
Porsche needs to quit misleading its customers and find a fix for those owners whose systems don’t’ work properly. And Planet 9 ought to consider correcting its link that say TPMS “communicates the exact pressure of each tire and/or their deviation from ideal pressure” and that it “does away with the need for regular air pressure checks at the servicestation, which often prove highly inconvenient.” Given the problems some have had, Porsche owners might consider heeding the advice of the National Highway Traffic SafetyAdministration which created the TPMS law and check tire pressure at least once a month using a manual gauge and factory specs and only rely on TPMS as a safety backup.
The following users liked this post:
Sam-g (12-07-2021)
08-24-2018, 08:37 AM
#11
Rennlist Member
My TPMS is also 3 lbs off. Always 3 lbs too low. Using my manual gauge, I put the tires at 37(f) and 40(r). Therefore, the display is at 34 and 37. Pressures readings are all cold.
But you are correct about the manual. The display is to be used as a guidline, not used for accurate reading of the tire pressures.
But you are correct about the manual. The display is to be used as a guidline, not used for accurate reading of the tire pressures.
08-24-2018, 01:18 PM
#12
Yes there is a solution. The reason the pressure is off is due to Porsche attempting to compensate the reading based on outside air temperature. It would be so much easier if they just reported the raw reading.
To fix the offset errors, you need to set the actual cold pressure in your tires to a specific value based on the current outside ambient air temperature then reset the TPM system. If ambient is 68F, fill the tires to 33psi and reset. But if ambient is higher than 68F, fill the tires to a value HIGHER than 33psi and reset. Likewise if it's cold outside below 68F, under fill the tires to a value below 33psi and reset the system. It works out to adjusting your initial tire pressure to 0.8psi per 10F above or below the nominal ambient of 68F, then resetting the system.
See post #6 here: https://rennlist.com/forums/997-foru...ml#post8657735
To fix the offset errors, you need to set the actual cold pressure in your tires to a specific value based on the current outside ambient air temperature then reset the TPM system. If ambient is 68F, fill the tires to 33psi and reset. But if ambient is higher than 68F, fill the tires to a value HIGHER than 33psi and reset. Likewise if it's cold outside below 68F, under fill the tires to a value below 33psi and reset the system. It works out to adjusting your initial tire pressure to 0.8psi per 10F above or below the nominal ambient of 68F, then resetting the system.
See post #6 here: https://rennlist.com/forums/997-foru...ml#post8657735
08-24-2018, 04:35 PM
#13
Track Day
Good timing on this thread, I've had the same warnings come up continually after bleeding air out at the track the other day. Wasn't exactly sure how to get it back to normal. Next time I'll reset at the track so I'm not driving around with the Flat Tyre warning the entire time!!
09-11-2019, 09:40 AM
#14
Pro
I am still wrangling with the TPMS. System info is 3# less that what I know to be true. So, cold tires produce a warning light. Worse, last weekend it said I had a flat tire. Pulled over and it was a perfect (for what I want) 33 front, 37 rear with hot tires.
I came across this, a guy who was dealing with the same problem on an 08 Caymen:
Innacurate TPM
https://www.planet-9.com/987-cayman-...-systems.htmlS Systems
10/2/2010
While some of you report accurate pressure readings on your TPMS systems I am one of the unlucky ones whose 2008 Cayman system is defective. The actual pressure readout is consistently 3-4 psi lower than shown with a calibrated manual gauge. Worse, during hot weather it frequently signals a false -4 psi alarm for one tire when the tire has lost no air at all is at factory spec, and is the same as the other tire on the same axle which signals no warning. Porsche’s solution is to overinflate all tires to reset the warning system.
The first time I called the dealer about the problem in 2009 I was told I needed to try “tricking” the system to avoid false alerts. The service writer said other owners had the same complaint and tried using a winter tire setting to fool the computer. He thought Cayman air pressure was supposed to be 35 front and 42 rear and was surprised when I said my door plate says 30 front and 37 rear. I later learned from his mechanic that the dealer had been overinflating several customer cars to shut off false alarms.
On the first dealer visit the mechanic and I cross-checked our manual gauges. My calibrated gauge and his certified gauge were within a half pound of each other and confirmed my TPMS’s low readout. He reset the system but the false warning soon reappeared.
On the second visit the dealer, under the supervision of the field rep, replaced all four sensors. No change.
On the third visit they kept the car for a week while they exchanged emails with Zuffenhausen. They replaced the RDK control unit. (RDK—Reifendruckkontrollsystem—German for TPM.) No change: The dash “actual” tire pressures still read 3-4 psi low. And the next time it got hot the TPMS signaled a false alarm. (When ambient temperature goes up so does tire pressure supposedly lessening the chance for a false alarm. A true alarm should sound when pressure goes down not up!)
The next summer (2010) I took the car to the dealer with the same symptoms—alarm on with a false -4 psi drop and same inaccurate pressure readouts. But this time the dealer and customer rep in Atlanta pronounced the system in good working order. They blamed me for using a manual gauge and factory pressure settings instead of the tell-tale readout. The mechanic, service manager, field rep and customer commitment specialists all told me I must not use a manual gauge to set adjust tire pressure but rely only on the dash “add air” readout (but not to use the actual pressure dash readout) and go through a process they call “zeroing”.
Here’s how zeroing works for those of you who haven’t heard it from your dealer:
• The low pressure warning signals an audible and visual alert. (A tire cross-section symbol with an exclamation point.)
• The dash “add air” warning shows a low tire. (For example, LF -4psi.)
• Ignore the readout that shows the “actual” pressure in each tire. (For example LF +32)
• With the ignition on and the ”add air” menu displayed, you add 4 psi to the LF even though a hand gauge shows it at factory specs and the same as the RF.
• Then, in my case, after adding air to the LF the display changes and shows the other three tires low.
• Zeroing involves going back and forth adding air to the other tires and checking the readout until all tires show --(zero).
The pressures end up 3-5 psi higher than the factory specifications on the door post plate and owner’s manual. I was told to ignore those recommendations. But the alarm goes off.
When I protested to the customer commitment specialist, saying my owner’s manual said to always use a manual gauge and did not describe the zeroing process, he emailed back: “To my knowledge our owner’s manual does not mention the use of a hand gauge.”
The factory rep was wrong. My manual says:
• p. 217: “Always use an accurate tire pressure gage when checking inflation pressures.” P. 217
• P. 234: “Checking tire pressure with a pressure gage 1. Remove the valve stem cap from the tire. 2. Press the pressure gage onto the valve stem. Note on operation: Do not press too hard or force the valve stem sideways, or air will escape. If the sound of air escaping from the tire is heard, reposition the pressure gage. 3. Read the tire pressure on the gage stem and compare it to the permissible tire pressure. This information can be found on the tire pressure plate or in the (owner’s manual) chapter Technical Data. P. 234
So the manual in print says use a manual gauge and go by the Porsche specs. Verbally, however, all of the Porsche reps up the chain of command all the way to Germany say don’t use the manual gauge and do not go by the owner’s manual settings.
When that advice is followed the tire pressures end up higher than required (unless you’re a lucky owner with an accurate system), resulting in a harsher ride, possible faster wear in the tread center and possibly longer braking distances. Worse, though, the TPMS system is no longer a backup because it is now dictating tire pressure specifications. If it gets even further out of whack the tire pressures could stray even further from factory owner’s manual specs.
Where TPMS has been mandatory in the United States since 2007, it has remained an option in Germany until next year. Even so Porsche owners’ forums in Germany, where I have done a lot of consulting, are chock full of complaints about their optional systems malfunctioning. An example: “Porsche RDK ganz großer Mist ... immer Fehler und das ständige gepiepse nervt. Taucht meistens auf, wenn Sie die außentemp ordentlich verändert. Das Porsche RDK ist zu fein abgestimmt und zeigt schon Veränderungen ab 0.1 Bar.“ What he says, essentially, that Porsche’s TPMS system is ****; that the continual false alarms are unnerving, and that Porsche’s system is too sensitive.
Porsche needs to quit misleading its customers and find a fix for those owners whose systems don’t’ work properly. And Planet 9 ought to consider correcting its link that say TPMS “communicates the exact pressure of each tire and/or their deviation from ideal pressure” and that it “does away with the need for regular air pressure checks at the servicestation, which often prove highly inconvenient.” Given the problems some have had, Porsche owners might consider heeding the advice of the National Highway Traffic SafetyAdministration which created the TPMS law and check tire pressure at least once a month using a manual gauge and factory specs and only rely on TPMS as a safety backup.
I came across this, a guy who was dealing with the same problem on an 08 Caymen:
Innacurate TPM
https://www.planet-9.com/987-cayman-...-systems.htmlS Systems
10/2/2010
While some of you report accurate pressure readings on your TPMS systems I am one of the unlucky ones whose 2008 Cayman system is defective. The actual pressure readout is consistently 3-4 psi lower than shown with a calibrated manual gauge. Worse, during hot weather it frequently signals a false -4 psi alarm for one tire when the tire has lost no air at all is at factory spec, and is the same as the other tire on the same axle which signals no warning. Porsche’s solution is to overinflate all tires to reset the warning system.
The first time I called the dealer about the problem in 2009 I was told I needed to try “tricking” the system to avoid false alerts. The service writer said other owners had the same complaint and tried using a winter tire setting to fool the computer. He thought Cayman air pressure was supposed to be 35 front and 42 rear and was surprised when I said my door plate says 30 front and 37 rear. I later learned from his mechanic that the dealer had been overinflating several customer cars to shut off false alarms.
On the first dealer visit the mechanic and I cross-checked our manual gauges. My calibrated gauge and his certified gauge were within a half pound of each other and confirmed my TPMS’s low readout. He reset the system but the false warning soon reappeared.
On the second visit the dealer, under the supervision of the field rep, replaced all four sensors. No change.
On the third visit they kept the car for a week while they exchanged emails with Zuffenhausen. They replaced the RDK control unit. (RDK—Reifendruckkontrollsystem—German for TPM.) No change: The dash “actual” tire pressures still read 3-4 psi low. And the next time it got hot the TPMS signaled a false alarm. (When ambient temperature goes up so does tire pressure supposedly lessening the chance for a false alarm. A true alarm should sound when pressure goes down not up!)
The next summer (2010) I took the car to the dealer with the same symptoms—alarm on with a false -4 psi drop and same inaccurate pressure readouts. But this time the dealer and customer rep in Atlanta pronounced the system in good working order. They blamed me for using a manual gauge and factory pressure settings instead of the tell-tale readout. The mechanic, service manager, field rep and customer commitment specialists all told me I must not use a manual gauge to set adjust tire pressure but rely only on the dash “add air” readout (but not to use the actual pressure dash readout) and go through a process they call “zeroing”.
Here’s how zeroing works for those of you who haven’t heard it from your dealer:
• The low pressure warning signals an audible and visual alert. (A tire cross-section symbol with an exclamation point.)
• The dash “add air” warning shows a low tire. (For example, LF -4psi.)
• Ignore the readout that shows the “actual” pressure in each tire. (For example LF +32)
• With the ignition on and the ”add air” menu displayed, you add 4 psi to the LF even though a hand gauge shows it at factory specs and the same as the RF.
• Then, in my case, after adding air to the LF the display changes and shows the other three tires low.
• Zeroing involves going back and forth adding air to the other tires and checking the readout until all tires show --(zero).
The pressures end up 3-5 psi higher than the factory specifications on the door post plate and owner’s manual. I was told to ignore those recommendations. But the alarm goes off.
When I protested to the customer commitment specialist, saying my owner’s manual said to always use a manual gauge and did not describe the zeroing process, he emailed back: “To my knowledge our owner’s manual does not mention the use of a hand gauge.”
The factory rep was wrong. My manual says:
• p. 217: “Always use an accurate tire pressure gage when checking inflation pressures.” P. 217
• P. 234: “Checking tire pressure with a pressure gage 1. Remove the valve stem cap from the tire. 2. Press the pressure gage onto the valve stem. Note on operation: Do not press too hard or force the valve stem sideways, or air will escape. If the sound of air escaping from the tire is heard, reposition the pressure gage. 3. Read the tire pressure on the gage stem and compare it to the permissible tire pressure. This information can be found on the tire pressure plate or in the (owner’s manual) chapter Technical Data. P. 234
So the manual in print says use a manual gauge and go by the Porsche specs. Verbally, however, all of the Porsche reps up the chain of command all the way to Germany say don’t use the manual gauge and do not go by the owner’s manual settings.
When that advice is followed the tire pressures end up higher than required (unless you’re a lucky owner with an accurate system), resulting in a harsher ride, possible faster wear in the tread center and possibly longer braking distances. Worse, though, the TPMS system is no longer a backup because it is now dictating tire pressure specifications. If it gets even further out of whack the tire pressures could stray even further from factory owner’s manual specs.
Where TPMS has been mandatory in the United States since 2007, it has remained an option in Germany until next year. Even so Porsche owners’ forums in Germany, where I have done a lot of consulting, are chock full of complaints about their optional systems malfunctioning. An example: “Porsche RDK ganz großer Mist ... immer Fehler und das ständige gepiepse nervt. Taucht meistens auf, wenn Sie die außentemp ordentlich verändert. Das Porsche RDK ist zu fein abgestimmt und zeigt schon Veränderungen ab 0.1 Bar.“ What he says, essentially, that Porsche’s TPMS system is ****; that the continual false alarms are unnerving, and that Porsche’s system is too sensitive.
Porsche needs to quit misleading its customers and find a fix for those owners whose systems don’t’ work properly. And Planet 9 ought to consider correcting its link that say TPMS “communicates the exact pressure of each tire and/or their deviation from ideal pressure” and that it “does away with the need for regular air pressure checks at the servicestation, which often prove highly inconvenient.” Given the problems some have had, Porsche owners might consider heeding the advice of the National Highway Traffic SafetyAdministration which created the TPMS law and check tire pressure at least once a month using a manual gauge and factory specs and only rely on TPMS as a safety backup.
LOL, that's some high quality customer service. I've run into this same issue with my new-to-me 2009 C2S. My TPMS readout is exactly the same as my manual gauge (30F/34R cold) but it's throwing a -5 psi error on the driver's side rear. Every once in a while giving a 'Flat Tyre' error.
It sounds like I can turn off the warnings with a Durametric. Anyone know how to do this? (Full disclosure, I don't have a Durametric and have never used one. So a recommended Durametric would nice, too.
)
09-11-2019, 12:00 PM
#15
Rennlist Member
