[Evilmoretea]

Collected new car 3 days ago.

Noticed this evening the presssures seem unbalanced left to right but consistent in the difference if that makes sense. Car is not sat on a curb or anything.

Sensor issue?

[Littlecoupe]

Since it's brand new as you state, I assume it was not filled evenly on both sides. I suggest filling all tires to your desired pressure, then monitor over a few days. This assumes you have not verified manually with a physical pressure gauge.

[Evilmoretea]

Originally Posted by Littlecoupe

Since it's brand new as you state, I assume it was not filled evenly on both sides. I suggest filling all tires to your desired pressure, then monitor over a few days. This assumes you have not verified manually with a physical pressure gauge.

Also I’m fat man I could just be putting more load on the drivers side (RHD) 😂😂
Don’t have my own pressure gauge but pretty sure the car came with one of those tyre repair kit type electric pumps. That should be accurate enough?

[BG42]

Originally Posted by Evilmoretea

Also I’m fat man I could just be putting more load on the drivers side (RHD) 😂😂
Don’t have my own pressure gauge but pretty sure the car came with one of those tyre repair kit type electric pumps. That should be accurate enough?

Buy a gauge whats the matter with you lol.

[Evilmoretea]

Originally Posted by BG42

Buy a gauge whats the matter with you lol.

Any recommendations

[M_Power Rob]

Can also be affected if one side of the car is in the sun and one side in the shade. The more important pressures are how they read once tires are warmed up.

[Pentland]

Originally Posted by Evilmoretea

Any recommendations

https://www.halfords.com/tools/garag...ge-171797.html

Originally Posted by M_Power Rob

Can also be affected if one side of the car is in the sun and one side in the shade. The more important pressures are how they read once tires are warmed up.

OP is in UK. It’s not down to sunshine at this time of year

[Evilmoretea]

Originally Posted by Pentland

OP is in UK. It’s not down to sunshine at this time of year

Speaking of Halfords, bummed they stopped selling auto finesse stuff.

Just hoped int the car and pressures were even across the board with some driving. Temps slightly higher on right side. All sounds good.

[RockCrusher]

Originally Posted by Evilmoretea

Any recommendations

Have several dial tire pressure gauges. The bigger the dial the better. Easier to read. Also I like the style that "remembers" the pressure so I can move the pressure gauge from the stem and bring up to read the dial.

Unfortunately all gauges in my cars and I can't recall any brand.

For new cars I almost invariably have to fuss with the tire pressures to get them all sorted.

It is important to strive to get the pressures the same. I am OCD when it comes to tire pressure differences. In my 230i and under way call up the tire pressure display it is with a sinking feeling I see tire pressure differences. Ok just 1 psi between the two front tires (35/36 and 1 psi between the two rear tires (39/38). But I remind myself to drive the car some. And after a bit the tire pressures update and because the car was parked in a garage all the tires are the same temperature and thus the pressures agree. 36/36 and 39/39.

You might look into taking the car to the dealer and asking for the tire pressures to be set. The techs have a tire gauge that can be set to a specific pressure and then the tire is filled with (or bled of) air to get the pressure spot on.

My sister has good luck with her X4 stopping at a nearby Discount Tire store and having the tire pressures set. Apparently this is a free service and she's quite happy with the service. And she's as OCD about tire pressures as I am. (You don't want to know the trouble I had keeping her (then) Infiniti EX35 tires properly inflated when we convoyed from CA to AR going from mild temperatures in the Central Valley of CA to Flagstaff (inches of snow on the hotel parking lot) then east. Spent more time fussing with tire pressures than driving...)

Pic of my M2's tire pressures. My 230i tire pressures are equally good (now) but I don't have a pic.

[Evilmoretea]

Originally Posted by RockCrusher

Have several dial tire pressure gauges. The bigger the dial the better. Easier to read. Also I like the style that "remembers" the pressure so I can move the pressure gauge from the stem and bring up to read the dial.

Unfortunately all gauges in my cars and I can't recall any brand.

For new cars I almost invariably have to fuss with the tire pressures to get them all sorted.

It is important to strive to get the pressures the same. I am OCD when it comes to tire pressure differences. In my 230i and under way call up the tire pressure display it is with a sinking feeling I see tire pressure differences. Ok just 1 psi between the two front tires (35/36 and 1 psi between the two rear tires (39/38). But I remind myself to drive the car some. And after a bit the tire pressures update and because the car was parked in a garage all the tires are the same temperature and thus the pressures agree. 36/36 and 39/39.

You might look into taking the car to the dealer and asking for the tire pressures to be set. The techs have a tire gauge that can be set to a specific pressure and then the tire is filled with (or bled of) air to get the pressure spot on.

My sister has good luck with her X4 stopping at a nearby Discount Tire store and having the tire pressures set. Apparently this is a free service and she's quite happy with the service. And she's as OCD about tire pressures as I am. (You don't want to know the trouble I had keeping her (then) Infiniti EX35 tires properly inflated when we convoyed from CA to AR going from mild temperatures in the Central Valley of CA [...]

Thanks so temps being slightly off isn’t something to worry about, mainly just pressure?

[Pentland]

Originally Posted by Evilmoretea

Thanks so temps being slightly off isn’t something to worry about, mainly just pressure?

Pressure varies with temperature. Each tyre will heat up differently as you drive.

Buy the gauge I suggested. Tyres should be set at around 10 degrees c ambient. Note: the tyre gauge will have a tolerance (the one i suggested has a narrow tolerance and is therefore quite accurate).
Each TPMS will also have a tolerance so there will anomalies on each tyre. I’d trust he gauge over the TPMS and accept that each tyre will heat up and the readings may be different as you drive.
In my case, TPMS and gauge give the same answers. Lucky I guess.

[M_Power Rob]

Originally Posted by Pentland

https://www.halfords.com/tools/garag...ge-171797.html




OP is in UK. It’s not down to sunshine at this time of year

Touche

[kuzdu]

what PSI do you guys keep your tires at? i do 38 in the front and 40 in the rear

[Pentland]

Originally Posted by kuzdu

what PSI do you guys keep your tires at? i do 38 in the front and 40 in the rear

2.5 bar all round per the door card.

[nype]

Make sure the correct tire type / size is selected in iDrive. Should match the door card of course. Mine did not initially. This will update in the app as well.

I just use the iDrive tire pressure monitor app when adjusting pressures. It updates in realtime.

[Evilmoretea]

Originally Posted by kuzdu

what PSI do you guys keep your tires at? i do 38 in the front and 40 in the rear

According to my TPMS 39 all round with recommended 39 front and 38 rear.

[Evilmoretea]

Hey Pentland I see some people mentioned that you can change the recommended tyre pressure if you drive at +100mph. I can’t find this setting in the tyre settings.

I have the m technology pack with the PS4S and wondered if that made a difference.

[nype]

Originally Posted by Evilmoretea

Hey Pentland I see some people mentioned that you can change the recommended tyre pressure if you drive at +100mph. I can’t find this setting in the tyre settings.

I have the m technology pack with the PS4S and wondered if that made a difference.

You have to choose the summer performance tires and the correct size and there was prompt for >100mph or <100mph when I set mine up.

[Evilmoretea]

Originally Posted by nype

You have to choose the summer performance tires and the correct size and there was prompt for >100mph or <100mph when I set mine up.

Thanks I didn’t want to start messing about with it but good to know the option is there.

Weirdly my recommended front pressure according to TPMS is higher than rear.
39 front and 38 rear

Also get hotter front temps. That normal?

[Pentland]

Originally Posted by Evilmoretea

Thanks I didn’t want to start messing about with it but good to know the option is there.

Weirdly my recommended front pressure according to TPMS is higher than rear.
39 front and 38 rear

Also get hotter front temps. That normal?

Yes. Front wheels do the steering so will have more friction.

[RockCrusher]

Originally Posted by Evilmoretea

Thanks so temps being slightly off isn’t something to worry about, mainly just pressure?

Yes. Just set the tire pressures when the tires are cold. For me this is after the car has sat overnight in an unheated garage.

Also I take into account the expected low temps forecast. It is not uncommon for me to over inflate the tires by several PSI because while the ambient air temperature is say at 50F the forecast calls for low temperatures of 20F or more degrees colder in a few days.

I use the ballpark number of 1psi change in air pressure per 10F change in temperature. Thus if the ambient air temperature is 50F but 30F temps expected I will have the cold (50F) tire pressures 2 even 3 psi higher. This way when the cold temps arrive the tires will have the correct cold air pressure.

I do this to avoid having to fuss with tire pressures as a cold spell sets in. And to avoid in the colder temps running the tires under inflated. It is not advisable to run tires under inflated.

The flip side is I'm not quite as quick to adjust tire air pressure as ambient temps climb. For instance my area has gone from pretty cold overnight lows in the single digits to overnight lows in the 40s. But I'm not messing with tire pressures just yet because these 40s will not last.

To state the obvious when one drives the car the tires warm up. For various reasons the tires may not warm up the same. In the case of my M2 apparently the left front tire frequently runs a few degrees warmer than the right front tire. (See attached pic.) This is apparently due air passing through a cooler (oil cooler I think) that tends to heat up the tire a few degrees over time.