I have a 1.2 TSI DSG with 16,000 miles on the 2010 reg.

I have been keeping my tyre pressure to 2.1 bars (30 PSI) as per what it says inside the petrol filling cap.

But recently I had the car in for it's second service and noticed that all the tyres were around the 2.5 bars (36 PSI)

I am confused as to why they would have done this.

Any ideas?

Should I reduce the pressure or keep it as it is?

If you are using your own pressure gauge, it might be over reading, ie 36 psi showing on yours might in fact be really 32. I would check with another gauge.

2.1 bar is 30.5 psi near as damn it.

Allied to this your guage may over read a couple of psi and the garages under read.

They probably put in a couple of psi to allow for the fact that most people don't check tyre pressures for months at a time,and tyre pressures very slowly drop.

I have wondered this with my 2.0l 110, the 2.1 figure always seems really sloppy on the road, so I have been putting in a little bit more, usually 2.3 and the tyres still look a little pudgy with an empty car.

Had a similar thing with my previous x-trail, the dunlop ST20's needed 2.3 instead of the advertised 2.1, and they would still always wear on the edge, indicating under inflation.

Are you checking the pressures when cold? Even a short drive will heat up the tyres and wheels and increase the tyre pressure, so unless you're checking them at the same temperature you will see variations.

2.1 bar is aprox' 30.5 PSI so I keep my tyres at 31 PSI on all 4 corners.

Are you checking the pressures when cold? Even a short drive will heat up the tyres and wheels and increase the tyre pressure, so unless you're checking them at the same temperature you will see variations.

I agree, I have always been taught to check tyre pressures within a mile of starting from cold and not travelling at high speeds.

Tend to always use the digital gauge at my local garage and was wondering the other day who checks it to ensure it reads accurately

More times than not I find that the car comes back from service with over inflated tyres and I have to adjust them down again. The 16 " 215/60 setup on a TDI 4x4 run at 2.2 bar, which feels just right for ride comfort with no more than a couple of people and light luggage.

TP

I agree, I have always been taught to check tyre pressures within a mile of starting from cold and not travelling at high speeds.

Tend to always use the digital gauge at my local garage and was wondering the other day who checks it to ensure it reads accurately

Local Trading Standards, but it depends how busy or overworked they are in your area. Around here they seem to get done at the same time as the pump volume checks, so reasonably often.

Local Trading Standards, but it depends how busy or overworked they are in your area. Around here they seem to get done at the same time as the pump volume checks, so reasonably often.

Interesting, Thanks for that, very good to know. It has always confused me that the best and most efficient pump locally is free, yet decrepit one's don't even get you thru all four wheels for your pound. Found one the other day, in a petrol station next to a skoda dealership that had no gauge at all!

That reminds me I have yet to check the spare, will it be the same pressure?

Edited 28 May, 201214 yr by angrybeard

Spare, same as the rest.

Blimey, you have to pay for air!!

Spare, same as the rest.

Blimey, you have to pay for air!!

Welcome to Kent!