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Old Jul 16, 2018 | 12:30 AM
  #1  
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Default noob TPMS question

I didn't bother to check the tire pressure till now can someone confirm my tires are over inflated and the normal should be all zero?
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Old Jul 16, 2018 | 01:13 AM
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Just a bit for what ever setting you have your car set to.

Is this cold tire pressure?

I have my 13 C4S set to comfort setting which is 32F 34R.
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Old Jul 16, 2018 | 01:41 AM
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I dunno, is "cold tire pressure" a setting or it is the pressure when car is cold and not moving?
btw, here is the spec:

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Old Jul 16, 2018 | 02:48 AM
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Take a look at the manual for a better understanding. The door jamb sticker shows full load cold pressures, i.e the tire is cold and the car is full of passengers and luggage. There is also a comfort pressure setting for part load, one passenger and no luggage, most run like this. Check the absolute pressures with a pressure gauge, or the dash or that phone app, rather than the delta from full or part load, they look like they're at full load pressures and then some.
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Old Jul 16, 2018 | 06:37 AM
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Don't know what model you have but door jam pressures are for a fully loaded car.
Cold tire pressures at comfort setting for my 4S and now my TTS are set at 31 f and 34 r. You will feel a major difference in ride quality at these settings compared to what you are running now.
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Old Jul 16, 2018 | 07:42 AM
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Originally Posted by _RS_
Take a look at the manual for a better understanding.
This. The door frame tire values are good for most cars, but Porsche does things a bit differently (better) with pressures specific to the conditions. Use the comfort settings, not the max speed setting - it's not a matter of "manliness", the lower pressures actually grip better in normal driving.

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Old Jul 16, 2018 | 09:14 AM
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2017-2018 911 Carrera

Standard tire pressure





Comfort tire pressure up to 165 mph (270 km/h)
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Old Jul 16, 2018 | 09:19 AM
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Updated numbers for the Carrera T and the GTS are in the "Good to Know" app (not sure they are that different, though). For some odd reason, I cannot get Rennlist to load on my iPhone so I cannot post those right now.

I use comfort, partly loaded settings on my 2018 911 GTS - 29 front, 33 rear, as per the owners manual.
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Old Jul 16, 2018 | 09:20 AM
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Unless you plan on driving above 165 mph, I would not use the standard settings LOL. The car will ride a LOT stiffer at the settings in the door jam (fully loaded, standard).
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Old Jul 16, 2018 | 11:24 AM
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Yep, those are massively overinflated. On that display (the one with delta +/- pressures), the tire temperature doesn't matter. The car is doing the math and reports the the pressure over/under-fill regardless of temperature.

I agree with Hurricane that comfort partial load works for fine for road usage... even driving that is reasonably aggressive for on the road. Once you set the car's settings for Comfort/Partial-Load, just increase/decrease pressure as indicated until you get zeros or maybe ones for the reported delta. I think you'll enjoy the new ride.

Note that you'll probably have to set it back down again each time after a dealer visit since they tend to fill to full load pressures.
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Old Jul 16, 2018 | 12:41 PM
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Originally Posted by StormRune
Yep, those are massively overinflated. On that display (the one with delta +/- pressures), the tire temperature doesn't matter. The car is doing the math and reports the the pressure over/under-fill regardless of temperature.

I agree with Hurricane that comfort partial load works for fine for road usage... even driving that is reasonably aggressive for on the road. Once you set the car's settings for Comfort/Partial-Load, just increase/decrease pressure as indicated until you get zeros or maybe ones for the reported delta. I think you'll enjoy the new ride.

Note that you'll probably have to set it back down again each time after a dealer visit since they tend to fill to full load pressures.
Heck I autocross and I still use comfort, partly loaded pressures! They seem to work well.
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Old Jul 16, 2018 | 12:46 PM
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Originally Posted by Hurricane
Heck I autocross and I still use comfort, partly loaded pressures! They seem to work well.
'
Yeah, I use comfort in autocross too and don't have any problem with edge roll even if the car slides. The slight bit of extra traction seems to be worthwhile.
I was referring to extended high-speed driving (aka track) when higher pressures are recommended to reduce heat buildup.
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Old Jul 16, 2018 | 07:42 PM
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Looks like you inflated for full load/max speed (which is what the sticker in the door jamb shows) but your system is set to look for "Comfort" settings. Just put them at whatever Hurricane's chart recommends for comfort settings and verify your PCM is set to "look" for comfort pressures.
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