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A few weeks back Brooner started a very informative post called 'DRC Goodwill no more' (link to the start of the topic: http://forum.rs246.com/viewtopic.php?f= ... &hilit=drc. I wondered if my DRC was a little under the recommended pressures as (imagined or real) my car's handling seemed overly sensitive to increased tyre pressures on hot days and windier roads. I wasn't sure how long it had been that way.

Service no.4 was due this week so I asked the the dealership to check the pressure while it was in. The DRC had never been touched since it left the factory five years ago, so (as per above topic) I assumed it would be a little down on pressure. The workshop manager advised me that I'd probably lose half a bar by measuring it - which he was happy to do - but suggested a full drain, flush and recharge would be a better idea.

The car was left in early so they managed to do the job by closing the same day, rather than keep the car overnight.

It turns out the pressure wasn't low at all - 13.5bar. I was hoping for a low pressure to explain away my handling worries. The final pressure post recharge was 15.5. Now that doesn't seem like much of a difference on paper to me but subjectively the car is feeling much better! The car's posture through tight cornering is much tighter and any lurch of the front corners when the car's weight is thrown at them is reduced. It's too early to say if the sensitivity to tyre pressures is cured but I'm optimistic.

So, what does everyone think? Could the DRC pressure increase from 13.5 to (edit) 15.5 be responsible? Is there something in the way a drainage, flush and recharge is done that might reset/correct damping issues?

...or is it all in my head?!

By the way, hats off to Tyneside Audi. We've had our run ins but everyone seemed to know what they were doing today. Would recommend.

13.5 to 15.5 is a pretty big difference, probably feel it
think of it as stiffer shocks

DRC system pressure values
These pressure values are based on a reference temperature of 20°C.
16 bar = Maximum pressure
15 bar – 16 bar = Central valve new or in as-new condition
12 bar – 15 bar = Normal working range; system OK
< 12 bar = System leaking or not fully charged; air trapped in system; central valve depressurised/empty.

13.5 is a good number (probably 14 before the 0.5 loss hooking things up to take the reading)

Yup, I could've just said stiffer shocks...

The dealership charged £100 (plus vat) altogether: £80 for the procedure plus twenty quid for the two liters of oil. I think it was worth it. And I got to drive an ibis white S-line 2.0 TDI B8 courtesy car for the day. Nice to compare/contrast. Please shoot me if I ever buy another four pot diesel.

Big road trip next week. DRC checked, little audio upgrade today, and new set of Dunlop F1 AS2's on before I go. Happy days.

IIRC the revised design on the RS5 uses even higher pressures...

Thanks, stu, for this feedback.

My Saloon is from January 2006 (probably December 2005 made, German origin, maybe one of the very first B7, supersport plus chassis=1BE Sports Suspension/Shock Absorption option).
When I bought it at 57000 km, the professional vendor did the 60000 km (37000 Miles) service at Audi Monaco. There was no leak on DRC.

Now, with 67000 km (10000 km/6200M in two years ), the next service is in less than one month.
At last, I will know if there is some leaking! (but no symptoms at all).

If no leak, what should I do?
1) By God, don't touch anything, leave it alone?
2) Do the same you did? with the risk that something goes wrong?

merlinus98 wrote: [...]
If no leak, what should I do?
1) By God, don't touch anything, leave it alone?
2) Do the same you did? with the risk that something goes wrong?

I was in camp no.1 until I read the previous thread. There's a very comprehensive explanation about hydraulic pressure and wear which argued a strong case for option no.2, and that's exactly what I did. I had no leaks, no oil marks whatsoever. No harm was done and the car has actually been improved. The 'if it ain't broke don't fix it' argument is also strong though!