[skw]

This morning leaving for work, it was 39 degrees (F) outside. A few mins into the ride in, I get the low tire warning for all 4 tires so instantly knew it was because of the temperature drop. Then it went to saying just the right rear was low so I pulled over at a gas station to double check. I keep a pressure gauge in ea car. I've been keeping all 4 at 35psi, this morning they were between 29 & 30psi. Getting onto the highway, it went back to all 4. So here's the dilemma, I chose not to add air as today is going to be almost 70 and the next few days will be mid to high 70's. Adding air now will put them too high later. Sucks because while the warning light is on, you're locked in Comfort. It doesn't let you select sport nor eco. Checked the pressure again when I pulled into work and they were all at about 33psi.

[DJ Rocc]

Originally Posted by skw

This morning leaving for work, it was 39 degrees (F) outside. A few mins into the ride in, I get the low tire warning for all 4 tires so instantly knew it was because of the temperature drop. Then it went to saying just the right rear was low so I pulled over at a gas station to double check. I keep a pressure gauge in ea car. I've been keeping all 4 at 35psi, this morning they were between 29 & 30psi. Getting onto the highway, it went back to all 4. So here's the dilemma, I chose not to add air as today is going to be almost 70 and the next few days will be mid to high 70's. Adding air now will put them too high later. Sucks because while the warning light is on, you're locked in Comfort. It doesn't let you select sport nor eco. Checked the pressure again when I pulled into work and they were all at about 33psi.

Can't you turn off TPMS in IDrive, under vehicle Status?

[marseille82]

Originally Posted by DJ Rocc

Can't you turn off TPMS in IDrive, under vehicle Status?

I don't think it's an option, at least not for MY2013.

[skw]

I wouldn't want to turn it off. Actually on my wish list to get it coded to show the numerical pressures for ea wheel. On the highway to and from work, I usually settle into eco-pro, then go back to comfort or sport when approaching the off-ramp. Staying in comfort though wasn't really an issue. Once the day time temp drops to 50-55 degrees is when I add air. And not too long after that is when the Blizzaks go on.

DJ Rocc, down in JA, these are issues you never have to worry about! And yes, that is jealousy you hear in my voice!

[F32Fleet]

Yep. I imagine all cars these days have the same issue.

[shivaswrath]

Fill to 38 so you don't have to deal with the drama.

[S4NoMore]

All this makes me actually wonder if Nitrogen fill is doing its job, even though I did see it de-bunked on the internet somewhere. My car came with Nitrogen in the tires and from mid 30s to mid 90s and now back to fall weather I've not seen any fluctuation and haven't had to touch the tires at all. I coded to see actual pressure about a month ago so I'll be keeping an eye on it.

[rking117]

Originally Posted by skw

...So here's the dilemma, I chose not to add air as today is going to be almost 70 and the next few days will be mid to high 70's. Adding air now will put them too high later...

well it doesnt really work that way. While you might get a rise in pressure of a couple PSI you wont get anything dramatic. If you normally add air to get the tires to 35 PSI then why dont you take them to 34 PSI now and then when it warms up you will see that the pressure might autoadjust to 35 for you. You might even see a difference after a long drive. As the tires warm up the tires will increase a couple PSI for you automatically.

as for me i am running 36 PSI in the front and 45 PSI in the back on my Z. i found that all four of mine were 28 the other day when it cooled down out. I am a stickler to that hard ride of 36/45 because of the performance of the tires. So i aired mine up to 36/45 that day and took a drive. Afterwards i checked them again and didnt require any adjustments. for th epast week we are in the 80* again and I am still good to go. no adjustments are needed.

Jsut remember a couple PSI wont affect your tires that much if any. Unless you are on the track i wouldnt be overly concerned of the difference.

[rking117]

Originally Posted by S4NoMore

All this makes me actually wonder if Nitrogen fill is doing its job, even though I did see it de-bunked on the internet somewhere...

Nitrogen is really a waste of time and money. There is simply no way to evacuate the entire tire of O2 before filling with NO2 thus never giving you the benefits of it. also the tire is porous so there is still always some measure leaking out even in nitrogen filled tires.

[skw]

Originally Posted by S4NoMore

All this makes me actually wonder if Nitrogen fill is doing its job, even though I did see it de-bunked on the internet somewhere. My car came with Nitrogen in the tires and from mid 30s to mid 90s and now back to fall weather I've not seen any fluctuation and haven't had to touch the tires at all. I coded to see actual pressure about a month ago so I'll be keeping an eye on it.

It was a while ago I remember seeing a comparison on filling the tires w/ nitrogen. The end result was that there was no way to get 100% nitrogen, it was still "contaminated" by some percentage of oxygen. Even so, it was shown that due to the temp drop side, the nitrogen filled tires still had a drop of psi but it wasn't as much as the tire filled with regular air. So the suggestion was that if nitrogen was offered for free, take it, but it wasn't worth paying extra for. And also to still keep an eye on your pressure.

Originally Posted by rking117

well it doesnt really work that way. While you might get a rise in pressure of a couple PSI you wont get anything dramatic. If you normally add air to get the tires to 35 PSI then why dont you take them to 34 PSI now and then when it warms up you will see that the pressure might autoadjust to 35 for you. You might even see a difference after a long drive. As the tires warm up the tires will increase a couple PSI for you automatically.

as for me i am running 36 PSI in the front and 45 PSI in the back on my Z. i found that all four of mine were 28 the other day when it cooled down out. I am a stickler to that hard ride of 36/45 because of the performance of the tires. So i aired mine up to 36/45 that day and took a drive. Afterwards i checked them again and didnt require any adjustments. for th epast week we are in the 80* again and I am still good to go. no adjustments are needed.

Jsut remember a couple PSI wont affect your tires that much if any. Unless you are on the track i wouldnt be overly concerned of the difference.

No track time here (possibly an auto-x soon if I can), just a DD. When I get home I may experiment and bump them all up to 39psi, tires will be warm from the drive home, and see how it goes between the temps in the morning and if it rides any differently.

[rickinaz]

I agree about the cold weather coming. It dropped down to 70 last night.

[chiefneil]

Originally Posted by skw

I chose not to add air as today is going to be almost 70 and the next few days will be mid to high 70's. Adding air now will put them too high later. Sucks because while the warning light is on, you're locked in Comfort. It doesn't let you select sport nor eco. Checked the pressure again when I pulled into work and they were all at about 33psi.

If you really want to, you can just reset the TPMS to accept the lower pressure so the warning goes away. Then add air later and reset again, or just run low pressure until the weather warms up as you indicated.

[BavarianFanatic]

Given the fact that there's such a huge swing at play (30-40 deg.) you know you're not really "low". Don't be a slave to the TPMS system. If you don't want to drive around with a warning because you know you're OK, then just reset it when it's cold outside.

However, since you said you typically maintain 35 in all 4, and you only measured 33 after your drive to work, you're probably a couple of PSI below the 35 mark that you previously set. Either air up once it's warmer or try to find a happy medium.

[nicknaz]

I would set to the pressure on the door jam when its cold and then allow the pressure to get higher when the ambient temp gets warmer.

There is a range of pressures in the manual, such as over 100mph driving, anyway and I think tire pressure a bit higher is more ok than being a bit lower

[DJ Rocc]

Originally Posted by skw

I wouldn't want to turn it off. Actually on my wish list to get it coded to show the numerical pressures for ea wheel. On the highway to and from work, I usually settle into eco-pro, then go back to comfort or sport when approaching the off-ramp. Staying in comfort though wasn't really an issue. Once the day time temp drops to 50-55 degrees is when I add air. And not too long after that is when the Blizzaks go on.

DJ Rocc, down in JA, these are issues you never have to worry about! And yes, that is jealousy you hear in my voice!

Lol SkW. Very true, but we do have our share of additional issues as well.

[ggrr8t]

Originally Posted by marseille82

I don't think it's an option, at least not for MY2013.

I have 328xi, I am pretty sure you can untick the box to monitor pressure.

[Professor///M]

It's better to be a hair overinflated than under inflated.

Agree with the nitrogen comment... it's only useful if it's free. They charge quite a lot of $$$ for refills, and at the end of the day, the little difference they make, does not outweigh the cost.


On these days, just do lots of burnouts.

[rking117]

Originally Posted by skw

When I get home I may experiment and bump them all up to 39psi, tires will be warm from the drive home, and see how it goes between the temps in the morning and if it rides any differently.

39 might be a little aggressive. the pressures i qouted are for my Z4 which has a little different tire pressure requirements. I would target the pressure on the door jam unless you are trying to track it in which case who cares about wear of the tire do what is right for traction.

[carzaddict]

i run with 35's all the way around