Check your tyre pressures!

[ph001]

Just a quick reminder to everyone to check your tyre pressures on a regular bases and NOT rely on the tyre pressure monitor on the E85 / 86. Long story short - hadn't checked mine with a gauge for 3 months or so, and just gave them a casual visual as I approached the car - all looked OK. Handling felt fine.

Driving home from work which luckily is only a few miles when suddenly the TPS light comes on. Pulled the car over and did a quick visual on all the tyres (in the dark). The rear right looked a little bit low but certainly not flat. So, got compressor out of boot and attempted to top it up...nadda...couldn't get any air into it at all, gauge on compressor read 0psi. Odd I thought. Made the conclusion it must be the valve that was faulty and completed the remaining 1 mile journey home at a snails pace with the hazards on.

Note these are 265/30/R19 non-runflat Goodyear Eagle F1.

Got it in the garage when arrived home and took the wheel off.... This is what I found



So basically wrecked!!! Went around and checked the pressures on all other tyres:

RL - 32psi
RR - 0psi (obviously)!
FL - 16psi
FR - 25psi

I may have been driving around for weeks like this and the TPS did not flag it.

Lessons learned:

1) The profile and sidewall on the Eagle F1's is such that even at 0psi the tyres don't appear completely flat. You can even drive on them to some degree (as I did)! Don't rely on a visual check!!!!

2) The TPS on the E85 is not very good!

3) It's cheaper to regularly check your tyre pressures than have to shell out £300 for a new pair!

4) Get your alignment checked (you can see the inside edge of the tyre is much more worn than the outside).

 

[skelters]

Also make sure you reset the TPS after you get the tyres to the correct psi.

Weekly check of the tyre pressure too.

I'm surprised that you didn't notice the tyre pressure differences just from driving as the Z4 is quite sensitive to incorrect tyre pressures.

 

[damok666]

I learnt this very lesson myself last month but not so severe as yourself. I'd been away at work for a little over 2 weeks so the Zed had been standing for that time. I noticed as soon as I got home the FL looked low so first call was the petrol station a little over a mile away for air.

FL 9 FR 15 RL 22 RR 24

And the same as yourself, no TPS light at any time.

 

[agrimes1989]

I learnt this very lesson myself last month but not so severe as yourself. I'd been away at work for a little over 2 weeks so the Zed had been standing for that time. I noticed as soon as I got home the FL looked low so first call was the petrol station a little over a mile away for air.

FL 9 FR 15 RL 22 RR 24

And the same as yourself, no TPS light at any time.

It’s not a true pressure monitor system . All it does it flag up a change in rolling speed (I think) across the same axle . Since yours was similar side to side this wouldn’t flag up I don’t think . They also don’t flag up till it’s lost around half it’s pressure Iv found . Certainly not a substitute for not checking your pressures .

 

[mmm-five]

It’s not a true pressure monitor system . All it does it flag up a change in rolling speed (I think) across the same axle . Since yours was similar side to side this wouldn’t flag up I don’t think . They also don’t flag up till it’s lost around half it’s pressure Iv found . Certainly not a substitute for not checking your pressures .

Correct, but it's also reset when the car has been parked overnight and driven the next day.

If it goes flat overnight, it won't have a 'before' figure to work with - only the one it creates in the first couple of minutes of driving - and then the variance will flag across the axle when it gets significant enough (I assume it allows a few PSI in case of differences due to hard driving, as mine's never triggered on track - even though the max pressures overall increased 4psi after a few laps, and one side was only 2psi higher).

In my case, the last time I had a warning it was about 5psi due to a sticking front caliper.

I don't know why the UK/Europe didn't get the same in-wheel TPMS as our cousins over the pond did?

 

[agrimes1989]

I didn’t know that about resetting the next day . That makes very little sense to me . Surely if we can get a radio to stay programmed , they could have managed something similar with the tyre system .

 

[ph001]

I didn’t know that about resetting the next day . That makes very little sense to me . Surely if we can get a radio to stay programmed , they could have managed something similar with the tyre system .

Yeh, seems very disingenuous to me. Any supporting evidence for this?

 

[mmm-five]

Yeh, seems very disingenuous to me. Any supporting evidence for this?

Sorry, only observational experience.

If you want to test it yourself...lock up your car this evening, then release some air out of two tyres on the same axle (at least 5psi), and go for a drive. Tell me if the TPS comes on to say 'change in pressure'.

Mine didn't when I had a puncture. When I stopped at a garage to check the slightly slow turn-in on fast right hand bends, the LHF tyre was 6psi lower than the RHS - and was fine the day before as I'd checked them all before a 300 mile round trip.

 

[saj77]

I have an aftermarket TPMS fitted to both my Zed and daily driver. Fantastic bit of kit apart from when the sensors get corroded to the valve stems

 

[mmm-five]

I have an aftermarket TPMS fitted to both my Zed and daily driver. Fantastic bit of kit apart from when the sensors get corroded to the valve stems D7BD0E73-FB6B-4B19-A134-D49C30C4C7DF.jpeg

You're 2 PSI down on the front left, but it's not flagged a warning - and it's showing different temps in all tyres - and putting both PSI & ºC next to 2 different figures.

Confusing :?

 

[saj77]

The pressures and temps change as you drive.

 

[mmm-five]

The pressures and temps change as you drive.

I understand that, but at what point would it give you a warning that you've lost or gained too much pressure...or does it rely on the user checking the display (which is obviously easier than checking the tyres themselves).

 

[saj77]

You can set alerts yourself for +\- so much PSI difference but I’ve not bothered as instructions weren’t the best. I just keep an eye on the screen

 

[mmm-five]

You can set alerts yourself for +\- so much PSI difference but I’ve not bothered as instructions weren’t the best. I just keep an eye on the screen

 

[Smartbear]

Have a good look at your wheel, the rim looks to be damaged in that pic :?
Rob

 

[enuff_zed]

Have a good look at your wheel, the rim looks to be damaged in that pic :?
Rob

I think it's the rim protecting bit of the tyre and the angle of the photo.

 

[NSM]

So whilst a little off topic, as Z4's are known to be pressure sensitive and knowing that the pressure gauge on my compressor was not very accurate I was using our 3 series to judge the appropriate numbers so I could have some idea for the Z. This in turn prompted me to get the 30+ year old tyre pressure gauge out from the bottom of the tool box and that gave further different readings, so off to the shops and the purchase of a digital gauge - again different readings, so off to the local garage - your probably ahead of me here - different again, not huge differences, apart from the gauge on the compressor but enough.

How do we really know what are the accurate pressures but the TPMS is just a warning system which unfortunately for ph001 has not worked.

My experience is a little different to other posts, the only time the TPMS has woken from its slumber was when one tyre went down to around 24 psi in mid flight, all good after I had wheels refurbed and new rear tyres.

 

[enuff_zed]

So whilst a little off topic, as Z4's are known to be pressure sensitive and knowing that the pressure gauge on my compressor was not very accurate I was using our 3 series to judge the appropriate numbers so I could have some idea for the Z. This in turn prompted me to get the 30+ year old tyre pressure gauge out from the bottom of the tool box and that gave further different readings, so off to the shops and the purchase of a digital gauge - again different readings, so off to the local garage - your probably ahead of me here - different again, not huge differences, apart from the gauge on the compressor but enough.

How do we really know what are the accurate pressures but the TPMS is just a warning system which unfortunately for ph001 has not worked.

My experience is a little different to other posts, the only time the TPMS has woken from its slumber was when one tyre went down to around 24 psi in mid flight, all good after I had wheels refurbed and new rear tyres.

Well, for what it's worth, I use the same digital tyre gauge for all the checks on my cars. It may not be accurate, but it is consistent. So I am confident that if it says there's a 2 psi difference it is going to be pretty accurate at that.
Therefore, it works well to ensure a correct balance between the tyres.
Trial and error has led me to the figures that work well for me, on my gauge.

So when I say I have 34 front and 36 rear and someone else says they think it should be 32 front and 34 rear then we could both well be using the same actual pressures, measured on different gauges.

In short, use the monitoring system to highlight big drops caused by punctures or damaged wheels.
Use a pressure gauge to set the tyres at what feels right for you.
Don't get too hung up on what the monitor then tells you it thinks.
Be a bit 'old school' and check your pressures weekly and before any longer journey.

 

[scootr]

So whilst a little off topic, as Z4's are known to be pressure sensitive and knowing that the pressure gauge on my compressor was not very accurate I was using our 3 series to judge the appropriate numbers so I could have some idea for the Z. This in turn prompted me to get the 30+ year old tyre pressure gauge out from the bottom of the tool box and that gave further different readings, so off to the shops and the purchase of a digital gauge - again different readings, so off to the local garage - your probably ahead of me here - different again, not huge differences, apart from the gauge on the compressor but enough.

How do we really know what are the accurate pressures but the TPMS is just a warning system which unfortunately for ph001 has not worked.

My experience is a little different to other posts, the only time the TPMS has woken from its slumber was when one tyre went down to around 24 psi in mid flight, all good after I had wheels refurbed and new rear tyres.

Well, for what it's worth, I use the same digital tyre gauge for all the checks on my cars. It may not be accurate, but it is consistent. So I am confident that if it says there's a 2 psi difference it is going to be pretty accurate at that.
Therefore, it works well to ensure a correct balance between the tyres.
Trial and error has led me to the figures that work well for me, on my gauge.

So when I say I have 34 front and 36 rear and someone else says they think it should be 32 front and 34 rear then we could both well be using the same actual pressures, measured on different gauges.

In short, use the monitoring system to highlight big drops caused by punctures or damaged wheels.
Use a pressure gauge to set the tyres at what feels right for you.
Don't get too hung up on what the monitor then tells you it thinks.
Be a bit 'old school' and check your pressures weekly and before any longer journey.

Or the same gauge at different tire temperature. I see 2 PSI difference when the sun has been shining on the tires for a couple of hours... For my UK friends sun shine is that bright stuff that appears between the showers and makes you throw up your hands to protect your eyes.

 

[mmm-five]

For my UK friends sun shine is that bright stuff that appears between the showers and makes you throw up your hands to protect your eyes.

s**t, I thought that was Security or the Police