irenesbob

I recently had to add air to my tires as the cold season approached. I checked the manual re: TPMS re-set and it seems to say you can do that while stopped. I am a bit confused since I believe the TPMS is based not on actual tire pressure, but on differences in the RPM’s of each tire. If this is true, I would have thought the TPMS function needed to be re-set while the tires were traveling along. Any ideas if it is OK to do it at standstill? Thanks.

mwar99

I believe that is the only way to do it. I don't think you can choose the option you need to while moving.

I'm guessing it resets and then recalcs the pressure when moving the next time. Just a guess.

irenesbob

Thanks - I set it and I'll keep an eye on it - whatever that means.
On this car (new 12/13) I followed the dealer's suggestion to put hydrogen in the tires for something like $60 with lifetime refills. Once about 3,000 miles ago I brought the car in and asked them to reset to 36 front, 38 rear since the sidewalls looked and the ride/handling suggested the pressure was low. I wanted to use only hydrogen and believed the BS that they do not lose pressure. Today the check TPMS light went on when I was out shopping and the outdoor temp was 35. I could tell none of the tries looked flat, so I drove the 4 miles or so home.
Later tonight I checked the pressure when the car had been in the heated garage for a few hours and they all read exactly 30 PSI. I highly suspect when I had asked the dealer to set them at a specific level, they simply bled them down to 30 all around or whatever it read (maybe 31 or 32) in summer. The SOB's - I should have known never to trust them, I have two portable compressors in the trunk and two tire gauges (including on expensive Moroso) and have always checked my pressures every other week for the last 45 years. On this car I believed the crap about Hydrogen being stable, etc. At this point I am inclined to believe they never put anything but air in them. Now to figure out how to steal $60 worth of snacks from eh customer lounge!
Maybe my mpg’s will start to go up.

miwung

I hope you mean nitrogen😀.

irenesbob

Yes, it was late when I posted. Also, since the AW site is very slow for me (realted to IE?) I type in Word and cut and paste my messages. Somehow spell check and my sleepy mind came up with hydrogen. - well, it is nitro I am bitching about - lol

keithl

There is a write up somewhere on the TPMS, but once reset it takes like an hour of driving for it to fully calculate all the various measurements it needs to accurately detect accurate pressure loose. I believe the first 15-20 minutes it gets most of what it nees, but it think it does some other calculations after that. What I have not seen mentioned is how it does that if you do not drive 60 minutes right after resetting, since you can have some variation if this 60 minutes spans more that one driving session that may span days. This is one of the reasons I prefer direct read out TPMS.

mwar99

That would fit with a situation I had where it took a couple of days before my warning went off because the dealership put all tires at the same pressure, when I had them staggered as per the manual prior to the visit...they never reset the TPMS

Brooklyn

Just picked my A6 up on Saturday and noticed the staggered air pressure. I'm sure to running 40psi all around on my cars. How are you finding tire wear with the staggered pressure? My car came with Goodyear Eagle F1's, with a manufacturer recommended rotation schedule of every 6k.

James517

With your car sporting the new vanity plates "Hindenberg" and it weighing less, it might well get better mileage. :-)

irenesbob

Good point. However, the damned thing might get too light and float away - or is that the much heralded steering issue??
Just to be on the safe side I am staying away from Lakehurst NJ - lol