Formentor front suspension (DCC) noise or clunks over speed bumps identified

[spezwend]

I have very annoing clunking noise in my Formentor from day one. Dealer said this is normal working suspension noises, but I finally identified it. It is 100% coming form shock absorbers. It is very easy to identify, just disconnect the DCC plug from the shock absorbers. The car is now absolutely silent over speed bumps and uneven roads, like it should be. So the noise is coming from poorly made Monroe shock absorbers. There is a design flaw or production error in the factory because if new shocks are fitted, they clunk also. Dealers info.

My Formentor is made in 05.2023 and have Monroe shock absorbers 5WA413032K, AVQ107, E46K5001, 23W172. Same DCC shock absorbers are used in Golf 8 R and they also make that same clunk noise. But some cars do not clunk or maybe the owners just can't hear it.

To test it, turn wheels all the way to the right, push down the plug's locking lever and pull the plug down wards. I fixed the plugs with cable tie for test drive.



I have checked Monroe e-parts catalogue and they have removed DCC shock absorbers from it. They were there few weeks ago. Something is going on. So let your dealer know if you have a clunking noise.

 

[pkaps]

Yes, over speed bumps I also hear this noise from day one, two years go, but I thought as I had no other issues from handling etc that this was just a normal fact. Guess its not normal at all. I will test it without the dcc and see. It definately seemed quite weird to me when I first felt and heard the clunking noises but never thought it was an issue as I had heard so many good reviews for this suspension.

 

[spezwend]

Do you know other cars with good brand shock absorbers that make any noises over speed bumps? I do not. Years ago I had old Mercedes with 300 000km on it with OE shocks that started to make the same clunking noise before the oil came out...

 

[KJA]

Well I used to have this clunk noise over speed bumps on Q3 TFSI 45 MY2020.
Most noticeable in cold weather.
Would go away after a bit of driving sometimes.
It also had DCC and monroe shocks.
It started seemingly after a year or 2 of ownership.
I thought it must be dry Springs and weather.
So far formentor is very quite and soft on suspension compared to my previous.
You disconnected just the fronts? Or all 4?
Thanks for identifying and isolating the issue good to know.

 

[pkaps]

From the noise it seems spring related or something being loose when the suspension is extended.
I'm trying to figure out the reason of the sound being gone after disconnecting the dcc.
Any suggestions?

 

[spezwend]

I disconnected only fronts, but I quess it would be enough to disconnect only one cable to disable DCC.

@pkaps there are electric solenoid valves inside the shock absorber to control the oil flow and they make that noise when the oil flow is restricted.

 

[pkaps]

Thanks, that explains it!
After reconnecting, the DCC worked again without need for any set up?

 

[spezwend]

Yes the DCC error on IC was gone.

 

[spezwend]

Looks like Cupra Leon ST with DCC is also affected. Found it in German forum:

Poltern Vorderachse

Hallo. Ich habe seit heute ein Poltern an der Vorderachse. Meine es ist vom Dämpfer rechts bei kurzen Wellen in der Straße. Hat das noch jemand?

www.motor-talk.de

 

[pkaps]

This is exactly what's happening. usefull post, so that we can relate our problem and possible fixes although nothing solid so far.
In mine the rattling sound is more evident in Comfort mode.
On Cupra or Sport mode is not that noticeable, maybe because of the shorter travel of the shock.
I always drive on Individual mode where I set the engine on Comfort and the DCC one notch below Sport mode. I think this is the best for everyday city/rural driving. When the suspension is on Comfort it is very noisy and unsettling over rough roads and bumps, so I never use it.

 

[spezwend]

Interesting. I have different experince - comfort mode, less noise - cupra mode, the worst - plugs disconnected, totally silent.

Maybe different production lines and settings: before siestata and after siesta.

 

[pkaps]

Mine is 04/2022 production.

 

[spezwend]

Or just remove fuse #47.

With the plug or fuse removed, the shocks are about 50% more softer than in Comfort mode.

Cupra Formentor Sicherungskasten Belegung | Tabelle aller Sicherungen

Cupra Formentor Sicherungskasten Belegung ➤ Wo sind die Sicherungskästen im Fahrzeug? ➤ Tabelle aller Sicherungen inkl. Ampere ➤ Tipps & Video

carwiki.de

 

[CupForm]

Haven't tried the DCC on Formentor, but I can say my (normal suspension) Formentor is by far the noisiest new car I ever drove when it comes to speed bumps, potholes, tram rails over crossroads... There's lots of clunks and rattles that aren't supposed to be there, as if some components are loose - not properly tightened... and it's been like that since day one! Sometimes it feels like something's about to break under the car - especially on the front axle. And I'm usually over-cautious when it comes to slowing down for speed bumps, bad roads or avoiding potholes.
To convince me that I don't have mental issues, I just returned from a trip where I drove a rental Peugeot 2008 (also new), and that one was incredible quiet over any kind of imperfections on the road - and it did see some very poor asphalt on few occasions. No noise whatsoever from the suspension - and that's for a car significantly cheaper than the Formentor! Overall, the 2008 has a slightly inferior soundproofing compared to the Formentor, but the suspension was pleasantly quiet - which sadly I can't say about my car.

 

[spezwend]

It is worth to check for rattle: bonnet adjustmet, ABS pump heat guard, coolant expansion tank, A/C pipes near front right wheel and additional radiator on 310hp models. I have fixed these issues/rattles and if I disable DCC, the car is completely silent. All these fixes done on a brand new car! I would say Seat/Cupra have serious quality control issues or they knowingly ignore to save some money.

 

[pkaps]

I believe the rattle is related only to DCC components. If it was something else the rattle would have been worse in sport/cupra mode setting.
I could only feel the rattle over bumps/rough roads in Comfort mode, in Sport/Cupra is almost non existent.
Then again for some the rattle is less in comfort mode, as I said I set the DCC one notch below Sport on Individual and I'm perfectly fine.

 

[spezwend]

@pkaps pull the fuse and take a test drive. Without power, the valves inside the shock are fully open. I suspect the noise is coming from the valves.

 

[Issey]

I have a Cupra Formentor VZ hybrid. I'm experiencing a clunking and rattling noise coming from the suspension. The dealer greased the suspension last October, and the noise disappeared for a few months. They greased it again this past May, but the noise returned after a few days. The noise occurs at low speeds on uneven roads. Could it be related to the DCC ?

 

[spezwend]

Pull the fuse #47 and let us know. Do you know where they added grease?

 

[CupForm]

The noise occurs at low speeds on uneven roads

Exactly the same behavior on mine, however I have the non-VZ PHEV, without DCC. At low speed on bad roads, or on those covered with stone, or when going over tram rails over city crossroads, at less than 20 km/h I feel/hear the front subframe of the car is falling apart. With several different cars (not to mention cheaper and older than this one) there's no alarming noise driving on the very same roads - so I'm sure that's not normal. Too bad we have a crossover that's quiet only when driven over mint condition asphalt!
BTW, the noises I'm hearing are not coming from the shock absorbers - I know how that's supposed to sound.