I have a 2006 C5 Estate, 2.0l VTR that becomes very noisy at motorway
speeds. The garage acknowledges this, but can't offer a solution. I was
wondering if there was a way around this very annoying problem and if so,
could somebody please advise me as to what I should do? Any help would be
much appreciated.
Adrian - 16 Apr 2006 18:15 GMT
> I have a 2006 C5 Estate, 2.0l VTR that becomes very noisy at motorway
> speeds. The garage acknowledges this, but can't offer a solution. I
> was wondering if there was a way around this very annoying problem and
> if so, could somebody please advise me as to what I should do? Any
> help would be much appreciated.
What *sort* of "noisy"?
Engine noise?
Transmission noise?
Wind noise?
Tyre noise?
Changes in different weather conditions?
Changes on different road surfaces?
Changes with speed?
drd - 16 Apr 2006 21:23 GMT
>> I have a 2006 C5 Estate, 2.0l VTR that becomes very noisy at motorway
>> speeds. The garage acknowledges this, but can't offer a solution. I
[quoted text clipped - 12 lines]
> Changes on different road surfaces?
> Changes with speed?
it's not easy to get good NVH (noise, vibration, harshness) characteristics
in an estate - generally they tend to be quite "boomy". Unless suitable
analysis and development is carried out during the design and validation
phases, it's not an easy thing to put right after the fact ...
as Adrian says, what type of noise is it? there may be some tweaks you can
perform that weren't cost effective for Citroen to do themselves ....
CommNet - 17 Apr 2006 13:58 GMT
First of all, many thanks for your replies. The noise is a very loud and
deep roaring sound that appears to come from beneath the car; possibly the
result of some vibration. It starts at around 85MPH and peters out at around
105-110MPH. Beyond 110MPH (around 5000 rpm) it becomes reasonably smooth and
quiet again. My business frequently takes me to the continent and very often
to, or across Germany, where speeds of 90-110MPH are very common. I hope
this info helps. Thanks again, Robert
>I have a 2006 C5 Estate, 2.0l VTR that becomes very noisy at motorway
>speeds. The garage acknowledges this, but can't offer a solution. I was
>wondering if there was a way around this very annoying problem and if so,
>could somebody please advise me as to what I should do? Any help would be
>much appreciated.
Adrian - 17 Apr 2006 16:24 GMT
> First of all, many thanks for your replies. The noise is a very loud
> and deep roaring sound that appears to come from beneath the car;
[quoted text clipped - 4 lines]
> speeds of 90-110MPH are very common. I hope this info helps. Thanks
> again, Robert
Does it vary according to road surface?
Could be tyre noise.
Has it recently started or has it always been there?
Mr Benny - 17 Apr 2006 19:45 GMT
>> First of all, many thanks for your replies. The noise is a very loud
>> and deep roaring sound that appears to come from beneath the car;
[quoted text clipped - 9 lines]
> Could be tyre noise.
> Has it recently started or has it always been there?
Could it be a noisy engine under-tray flapping around or catching air?
. - 17 Apr 2006 17:06 GMT
> First of all, many thanks for your replies. The noise is a very loud
> and deep roaring sound that appears to come from beneath the car;
[quoted text clipped - 10 lines]
>> and if so, could somebody please advise me as to what I should do?
>> Any help would be much appreciated.
can you /feel/ any vibration ? have you swapped the rear wheels with the
spare, one at a time ? you may have a defective tyre. also, does your
C5 have an engine undertray ?if so, is it secure as they hum and flap
and can cause quite severe vibration if they get damaged.
CommNet - 17 Apr 2006 23:02 GMT
Thanks again for your replies. I can confirm that tyre and engine noise had
been eliminated. The noise may vary slightly according to road surface, but
it's heard to gauge since most of my driving is on motorways where the road
surface does not vary that much. I had this car from new. I was running it
in carefully, according to the manufacturer's instructions, so I didn't
increase the speed beyond 70MPH until the first 1500 miles. I had a BX, a ZX
and an XM before, but I'd never experienced this kind of discomfort with a
Citroen. Could this be an inherent design problem with the C5? Thanks,
Robert
/
>I have a 2006 C5 Estate, 2.0l VTR that becomes very noisy at motorway
>speeds. The garage acknowledges this, but can't offer a solution. I was
>wondering if there was a way around this very annoying problem and if so,
>could somebody please advise me as to what I should do? Any help would be
>much appreciated.
Adrian - 18 Apr 2006 08:07 GMT
> Thanks again for your replies. I can confirm that tyre and engine
> noise had been eliminated. The noise may vary slightly according to
[quoted text clipped - 5 lines]
> but I'd never experienced this kind of discomfort with a Citroen.
> Could this be an inherent design problem with the C5? Thanks, Robert
I doubt it.
Have you checked the engine bay undertray?
CommNet - 18 Apr 2006 16:18 GMT
Well, I've checked the under-tray. It is not loose because of a missing
screw, clip or clamp, however it is a big flexible plastic under-tray that I
imagine the wind can play real tricks with. I found that it is held in place
by just a very few screws and they are placed far apart, leaving wide gaps
for the plastic tray to rattle freely. I've added one extra screw in the
middle at the front of the tray, closing a very wide gap. I think this might
have just done the trick. Thanks again for your advice.
>> Thanks again for your replies. I can confirm that tyre and engine
>> noise had been eliminated. The noise may vary slightly according to
[quoted text clipped - 9 lines]
>
> Have you checked the engine bay undertray?
olddog - 19 Apr 2006 23:47 GMT
I had the same problem with my C5 estate. Until it built to a crescendo,
then splat ! The undertray dissapeared, fractured & fell off, at about 100
mph or so. No more noise. I'd take it off if i were you. Mine is fine now.
Cheers. Ray
> Well, I've checked the under-tray. It is not loose because of a missing
> screw, clip or clamp, however it is a big flexible plastic under-tray that
[quoted text clipped - 17 lines]
>>
>> Have you checked the engine bay undertray?
drd - 22 Apr 2006 09:25 GMT
<snip>
>> Could this be an inherent design problem with the C5? Thanks, Robert
>
> I doubt it.
I admire your faith in the automotive engineering industry ...
8-)