Help - just had blow out on m40 near beaconsfield

[bboy]

Tyre variants are
AO - Audi only
MO - Mercedes only x 2
Run flat and generic

Apparently they all have slightly different compounds but same dimensions and ratings.

As for ignoring TPMS warnings - guilty. Recently everytime the temperature has gone below 4 degrees I have been getting the red warning. I checked the tyres each time and they were fine so i reset the system. I must admit I just thought it was playing up again because of the temperature. The alert came on just after joining the motorway so i was wary of any change in car handling and there was none. Even after 50 miles the car was still driving fine and not pulling anywhere. Another lesson learnt, if in doubt pull over and check.

[neckarsulm]

As for ignoring TPMS warnings - guilty. Recently everytime the temperature has gone below 4 degrees I have been getting the red warning. I checked the tyres each time and they were fine so i reset the system. I must admit I just thought it was playing up again because of the temperature. The alert came on just after joining the motorway so i was wary of any change in car handling and there was none. Even after 50 miles the car was still driving fine and not pulling anywhere. Another lesson learnt, if in doubt pull over and check.

I'd be interested to know what was causing the false alarms as there must be a reason, the TPMS is quite simple and quite effective IMHO, it does need VAG COM to be able to troubleshoot it though.
All the time it keeps quiet (without false or real alarms) I can rest assured the tyre pressures are correct, quite often I just get my car out of the garage and don't walk around it so I could easily miss a flat.

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Also with such wide low profile tyres a significant drop in pressure wouldn't always be obvious as a quick glance

[PetrolDave]

Also with such wide low profile tyres a significant drop in pressure wouldn't always be obvious as a quick glance

100% agree.

When I had a nail in a tyre about this time last year the TPMS showed a red warning but a cursory glance showed no visible difference between the 4 tyres. Only checking the pressures located which tyre it was, and on jacking the car up and using the "Mark 1 eyeball" was the problem visible.

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Would be nice if the TPS said which wheel was down but on the other hand it forces you to check all four.

[andre3k]

PetrolDave - where did you get a 19" space saver from and what jack do you use?

It's an 18" space saver that I bought from my local Audi dealer, fitted with a Continental space saver tyre. Remember the RS4 could be ordered with 18" wheels so it fits OK over the front calipers, and it has a rolling radius within a few mm of the OE tyres.

I use the genuine Audi jack, also bought from my local Audi dealer, which fits in the "wheel well" to the right rear of the battery. I modified the plastic with the aid of a Stanley knife so it fits neatly in there.

Can someone please explain this to me?!? I ran the tyre sizes (125/70-18, 255/40-18, 255/35-19 & 275/30-19) thru a calculator & the numbers churned out are a ways off?!?

http://www.miata.net/garage/tirecalc.html

[bboy]

Would be nice if the TPS said which wheel was down but on the other hand it forces you to check all four.

Totally agree. There is a sensor for each wheel so it should not have been hard to change the alert to something wheel specific.

I wonder if there is further information logged in VAG-COM?

['R'e'S'pect_4]

ordered my jack,

in on Tuesday.

£25

Cheers.