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Hello all, I’m a new owner, had my RS4 a week now and I love it!!

Cleaning it today I noticed my left exhaust flap open, the right one closed. It was last used in Dynamic. The right one feels really stiff.
What should it be like?

Thanks in advance and sorry if it’s a daft question.

Just seen something on the B7 forum that explains everything.

Now need to soak them in wd40 and hope they start working

Common problem I’m afraid.
Difficult to fix and a dealer will want to sell you a new rear box assembly.
Should be able to rotate them with your fingers, also worth spraying with a lube periodically.

mine were solid. a few weeks of wd40 and hitting it with a screwdriver has freed them off

Thanks guys. 1 can of isopropyl and 1/2 can of STP carb cleaner they’re starting to free up. I’ll carry on over the weekend and see what happens. £20 on spray is better than a new back box

Yup my thoughts exactly.
just seems to be the left one for me. dont know why

Seemed to have freed themselves up and are operating g as expected.

AndyBrad wrote: ↑

Wed Apr 26, 2023 3:23 pm

mine were solid. a few weeks of wd40 and hitting it with a screwdriver has freed them off

Did it smoke like a bastard after a full beans session because of the WD. Because mine just did. And im really hoping its the WD40 lol. Smelled like it.....

yup and the releasing fluid, and the ipa, and the 3in1

Had the same thing a year or so back.
Wd40 plus grease on the actual arm did the trick and been fine since.

Tip is to regularly open them so they don’t seize.

Set engine noise to dynamic in the individual setting in mine and select that for most drives. Gives you the best sound and prevents this problem reoccurring- win all round!!

One of mine is seized. I have manually reprogrammed it with a crowbar to always open. Much better now . I'll spray it everyday, maybe it will work again one day.

I think the problem is the actuator closes it and it starts in comfort so it always tries to close it. The spring then isnt man enough to open it once its shut.

Agree, the springs on my B9 valves are noticeably stronger the those on the B8 rear boxes.
When parking it in the garage you get a real metallic clack when the ignition is turned off.

Rusty Racer wrote: ↑

Sun Jun 18, 2023 7:09 pm

Agree, the springs on my B9 valves are noticeably stronger the those on the B8 rear boxes.
When parking it in the garage you get a real metallic clack when the ignition is turned off.

Is is possible to change the springs?

Im just wondering if running (in individual) setting the exhaust to comfort but the box to dynamic will help as every time you drive it will go above 3k and open the flaps and then close as you come to a halt?