DRC information PLEASE!!

[dutchbarge]

Hi, i am new to your website, but have been reading all your intresting comments over the past few months, only because i recently purchased a 2007 RS4 B7 saloon from Bradford Audi in december 2009, which i am totally pleased with after searching 6mths for the right spec'ed one, BUT i have noticed a knock when i go over speed humps, and bumps in the road, and everybody mentions this DRC problem, what are the symtoms if there is a problem with the DRC? i had it into wakefield Audi 3 week ago and they could'nt find a problem with the car, but the knocking is still there, just wondered if this is what the knock could be? any information would be much appreciated?

[P_G]

Does the knock come from the front or the rear?

If rear could be DRC, but could also be loose exhaust back boxes.

DRC that is faulty can be seen on the shocks as they will have be covered in fluid and look wet. Those that have had fluid and it is now dried is not leaking DRC.

Knocking can quite simply be down to low pressure in the DRC system rather than it being broken. Audi say minimum tolerance is 12 Bar but it should be 14 Bar as I had knocking at 12.

[dutchbarge]

Hi P G
Cheers for the response, the knock definatly comes from the front.

There is no oil leak around the shockers

But the noise does seem to be a shocker, as when the wheel hits the speed hump the noise does not occur, it is only when the wheel is leaving the bump the noise occurs, as if it is when the shocker is extending (if it is the shocker).

I am taking into Audi this week, as when i took it there 3 week ago they found a stone guard which is cracked, they are replacing it to eliminate the noise being this, also a recall (oil pipe clip) but would they have checked the pressure of the DRC system to eliminate the knocking?

Is knocking, the main symtoms of a problem in the DRC??

[larshs]

Hi P G
Cheers for the response, the knock definatly comes from the front.

There is no oil leak around the shockers

But the noise does seem to be a shocker, as when the wheel hits the speed hump the noise does not occur, it is only when the wheel is leaving the bump the noise occurs, as if it is when the shocker is extending (if it is the shocker).

I am taking into Audi this week, as when i took it there 3 week ago they found a stone guard which is cracked, they are replacing it to eliminate the noise being this, also a recall (oil pipe clip) but would they have checked the pressure of the DRC system to eliminate the knocking?

Is knocking, the main symtoms of a problem in the DRC??

I had exactly the same problem, no noise when hitting the bump only when the wheels are leaving it. Replaced a leaking shocker an refilled the system fixed the problem.

[dutchbarge]

Hi P G
Cheers for the response, the knock definatly comes from the front.

There is no oil leak around the shockers

But the noise does seem to be a shocker, as when the wheel hits the speed hump the noise does not occur, it is only when the wheel is leaving the bump the noise occurs, as if it is when the shocker is extending (if it is the shocker).

I am taking into Audi this week, as when i took it there 3 week ago they found a stone guard which is cracked, they are replacing it to eliminate the noise being this, also a recall (oil pipe clip) but would they have checked the pressure of the DRC system to eliminate the knocking?

Is knocking, the main symtoms of a problem in the DRC??

I had exactly the same problem, no noise when hitting the bump only when the wheels are leaving it. Replaced a leaking shocker an refilled the system fixed the problem.

Cheers larshs, good to know, looks like thats what it most likely is, least i can put this to them when i take it in!

[gurj001]

Mnes just gone into Stealership this morning for the same issue, front shockers knocking when going over small steep speed humps (like the ones in McDonalds car parks, its the only place i I've seen this style of speed hump other than work car park)

They did say something about a oil return pipe chafing issue on there bulletin which they will be looking at.

Shocks were highlighted on the MOT / healthcheck, technically they're not what Audi would class as 'leaking' but the Master tech advised that he would replace them anyway as he could not find any other reason for the knocking. He said my car was fitted with the revised shocks already, but obviously there still seems to be an issue with these failing.

[dutchbarge]

Took it in wedesday just gone to Audi Wakefield, for a stone cover replacing, and a oil pipe that add a recall on it, it needed clamping, (i believe Audi has add a few bust in the same place on the RS4) and to look at the shockers!

I picked it up Wednesday teatime it was still on the ramp when i arrived, the lady at the service desk told me they had replaced the stone guard and done the clip fo the oil pipe, and the technician was going to have a word with me about the shockers, 15 minutes later he came out and told me the shockers would need to be re-pressurised, the down side the ride would be harder?? so it was booked in for next thursday!

As it was dark when i got home, in the morning i got under the car to have a look at the stone guard they replaced, confused because the stone quard had'nt been replaced, so i contacted Audi,but the lady who had booked it in was seeing to a customer, and she would ring me back, after 1 hour she called me back,and said didnt the technician mention it the new stone guard got broken in transit so we could'nt do it, which i amazed as i was sat with the lady when i picked the car up and she stated it had been replaced, so i said cancel next thursday, i will take it to Audi Bradford were i purchased the car to do the shockers, i lost all faith in Wakefield Audi, so hopefully they will re-pressurise the shockers.

[P_G]

Repressurisation is usually done overnight, i.e pressurised in the afternoon, left overnight, driven in the morning, checked and topped up if necessary. It's not usually done in one day beacuse it doesn't normally give the system time to equalise.

[dutchbarge]

Cheers PG good to know, i will see what Audi in Bradford have to say, all i know is that everybody mentions with the RS4 the DRC problem, the car is superb alround, its just when ever i go over bumps i get the knock, the car as only got 15,000 miles on FASH 1 owner, 2007, its immaculate throughtout other than this knocking on bumps, best keep to the flat roads!!! for now!!

Cheers for the replay PG anyway.