deputydog95

I thought it might be helpful to know when the tires had heated up to optimal pressure.

As it turns out, the system couldn't cope with it. I started out with 27 psi and ran all day at around 37-38 psi per analog pressure gauge (R888 tires).

Despite the fact that my analog gauge was reading 37psi, my dash readings stayed steady at around 31 psi. Way off....

And on top of that, it was giving me a dual rear flat tire warning all day. Even after I increased pressure for the ride home.

I'm not sure if its the heat or what, but dash display wasn't anywhere near close to accurate under track conditions. When I get some track wheels, I will most certainly not install the TPMS sensors. Waste of money....

johnr265

Hmmm, that's odd. Mine seems to work fine on the track and in fact, I have found it to be very accurate. May want to have the dealer check it out. I love having it on my car and I ordered my track wheels with it too.

roberga

mine works great.

Z06

I had trouble as well, still important to have considering we don't have a roll bar incase we loose air on the fly! I check my tire pressure every lap!

roberga

what is VERY important is on the street. I had a puncture and the system caught it before the tire and or wheel were damaged.

TRAKCAR

OK, I'm clueless what this all means, but I had 2 flat tire warnings with RA1 this weekend:

The first time, I ignored it, then I got the message TPM partially monitoring and my left rear tire pressure went from 34 PSI (The rest was 37 PSI) to --.

Cool, no problem, until the car turned on SC and TC!! Now I am annoyed. So I de-active them again and continue on, the car get more and more loose on right handers, so I go in. Next morning I check the tires and all are around 24PSI, but out I have a nail in the left rear tire and I am at 15 PSI. OK, maybe TPS and a smart car is not so bad after all.

Then I put a new wheel with new tire on (I got plenty of 'em now right?! Thanks Mooty), but for some lazy reason I decide to go out with 27PSI in that tire and leave the rest at 24PSI. I start driving all temps go to 37PSI, except the left rear shows 30PSI and gives me flat tire warning and then goes to -- but SC and TC do NOT come on. So I think maybe a flat tire again??!! I go in the pit HOT, smoke billowing and check pressures all around, all tires were 38, so only 1 PSI higher than the dash says, but my left rear is 40, Makes sence since I started 3 PSI higher, but that was 10PSI higher then the dash said before it went to -- with a flat tire warning..

All in all, I still like it, you can see pressure build up, but it is far from perfect and not sure the $500.00 per set. I have many times where the rear tires go -- and I get a flat tire warning, also when there is no flat tire!

I am going to research to see if the parameters can be adjusted, so that the flat tire warning comes on only with a real flat tire.

MJones

There is a difference between gen 1 & 2 TPMS.

Gen1 covers MY07-08 and is a POS.Takes forever to update.

Gen2 covers MY10-11 and is pretty good with updates.

BBTurbo

I found that once you go below 27 psi or so on the track, the TPMS has a hard time catching up. I generally have to reset the system. Basically tell it to relearn the sensors or else I get a -- or flat tire warning. If I keep the tires at 28+ cold no issues.

deputydog95

Maybe it had something to do with the heat at Sebring this weekend since we both had problems with the TPMS system. It was insanely hot outside and I have believe tire temps were easily in the 180-200 range. It makes no sense whatsoever that the rears are reading 33psi per the dash and I'm getting a flat tire warning for both (dash read minus 7psi or something like that when you went into the messages). I saw almost no buildup whatsoever on the track. It got to around 31 psi and did not read any higher.

I'm tempted to go outside some night this week when its cooler and inflate the tires to 40 cold per my gauge and see what the dash reads.

How often does the TPMS read the pressure anyway? Does it refresh instantly or is it once a minute, etc?

deputydog95

I'm in Gen 1 so that may explain it

deputydog95

How do you reset the sensors? Even on my drive home after I added air to the tires I'm still getting the damn flat tire warning.

27psi is kind of high for a flat tire alert considering the fronts only require like 31 psi. It would be nice if the warnings were user programmable.

BBTurbo

You go into the tire menu with your lower left hand stalk and switch to snow tires and then back to summer tires. The system will say TPMS inactive, learning. Then it resets.. Generally it says flat tire when you go -5lbs. So if I run at 27 on the rears I may see a flat tire warning. In my experience 27 is low enough that the TPMS has a hard time. Usually 3 of the 4 tires will be OK, but one of the rears will get flaky.

deputydog95

So if I start at 28, and bleed off I should be okay? I'd really like to use the system if I can get it to cooperate.

Jake951

I also find TPMS pretty useless on the track. I've found it reads as much as 7-8 psi too low when the tires are hot. The most annoying thing is when it flashes a warning that the tires are underinflated when I've let out air to bring the hot pressures to the right range, using a real gauge.

BBTurbo

Unfortunately I can't give you exact numbers, you'll have to play a bit. My tires like 27F & 28R when cool. But due to the sensor issues, in general I start off at 29 front and 30 rear on my first run and then drop two pounds out of each tire when I come in. This will usually let the TPMS run ok for the day. But if there is a long wait between runs or if the track is real cool you may still get the error.