D3 Strange noise from engine bay

[austeve01]

I have a 2007 D3. At around 1500 to 2500 rpm I get this noise that sounds like a bunch of cicadas has descended on the engine ... irritating to say the least. Vehicle doesn't seem to lack performance. I thought it could be a bearing of some description on the way out but really I have no idea. Anyone with any clues here your input would be appreciated? Thanks :confused:

[Graeme]

Could it be the common split in the I/C hose that's only just started so hasn't particularly affected performance yet?

[Ivan]

Had a similar thing on my D3 V8. Turned out to be things in the lower glovebox rattling.

Ivan

[oldsalt]

Had any work done on the car lately ? - if so, check if they have left any tools laying about in the engine bay... happened to my wifes car a while ago and it drove me nuts till I had a good look around and found the "offending" tool which should have been in the mechanics toolbox and not on the engine bay.
Other than that I've no idea I'm afraid as my 2007 is just ticking over as usual - no cicadas in my engine bay

cheers

[TerryO]

It sounds pretty much like a bit of a bizarre noise my D3 often makes, the thing that really annoys me is no mechanic has ever been able to diagnose or fix it, even though they can hear it. Like yours while the noise is very annoying it hasn't affected performance.

Please let me know if you get to find out what the problem is.

cheers,
Terry

[sniegy]

Can you record it & post?

Sent from my iPad using Forum Runner

[connock]

Does the noise only happen when driving at those RPMs or can you make it do it by reving your car (to the lower rpm of coarse). If it makes the noise from just rev you could stick your head under the bonnet to try to find it.
Just a thourght

[justinc]

cicada noises are usually associated with failing belt tensioners. take a look asap before it leaves you stranded :(

jc

[austeve01]

Thanks Graeme. I had the i/c hoses checked and the mechanic said they were all in good order but he did tighten them.

[austeve01]

Thanks Ivan. Pulled everything out of both glove boxes but alas to no avail .. the 'cicadas' are still hanging around.

[austeve01]

Thanks for the input Old Salt.
I haven't been able to find anything in the way of tools in the engine bay & the mechanic had a quick look after he finished the service but couldn't find anything & reckons he not missing anything.

[austeve01]

Thanks Terry for your thoughts .. there was initially a suggestion from the mechanic that it may have something to do with the auto transmission (torque converter) but the AT has been serviced (steel pan & flush) and seems to be very smooth changing up and down effortlessly. I did notice for a very short time that the noise went away after the old alternator was replaced with a new one .. but the noise is back.

[austeve01]

Sniegy, I will give this a try but could be tricky as the noise is only heard whilst driving. If I try to replicate the noise whilst stationary there's no sign of the 'noise' at all.

[austeve01]

Thanks for your thoughts Connock .. it only happens at those revs whilst driving.

[austeve01]

Thanks Justinc. Now you mention it I will investigate this. Actually our Td5 had a problem with an idler arm pulley which was making a weird noise. It eventually seized and left us stranded for 24 hrs out the back of Lithgow.

[TerryO]

Ours mainly makes the noise when the engine is under load when driving, it also happens occasionally on over run when you just lift your foot off the gas for a second or two.

I too wondered about the belt tensioners and pulleys, but they were checked and one replaced, which did improve it for a while I must admit.

cheers,
Terry

[Rich84]

My 08 RRS TDV6 makes the cicada noise in exactly the same circumstances as Terry has described. Under load around 2500rpm and briefly on overrun sometimes. 163K on the clock and just getting parts required to do timing belt (I enjoy doing my own mechanical work), so I'll inspect all the pulleys when I remove them.

[TerryO]

I had a new timing belt fitted only 10k ago so that shouldn't be the issue, does sound more and more like the pulleys/tensioners.

cheers,
Terry

[Geedublya]

Mine does the same.... It has done it since I got it 40K back.

Haven't been able to find anything. New motor 50K ago, transmission rebuilt 10K ago.

I thought it might be one of the shields underneath vibrating.

[Nomad9]

Hi austeve01,
Just a thought, when you had the alternator replaced did you also replace the serpentine belt? I had a similar issue on my wifes car, when the alternator was replaced as part of a battery that was less than serviceable event. When the alternator was replaced a noise that was there before disappeared and then returned a couple of weeks later, I replaced the belt and re tensioned (no auto tensioner) the belt and the noise never came back. Just an idea.

[austeve01]

Terry what you describe happening here with the noise becoming apparent under load etc is exactly as it occurs with our vehicle. I also had new timing belts done about 15000k ago but still got the noise.

[austeve01]

Hi Nomad9,
The serpentine belt was not replaced because it was still in good condition but as with your experience the noise disappeared & returned a couple of weeks later. I think I will do as you have done & get the belt replaced & re tensioned and see if that removes the 'cicada noise'. You mentioned 'no auto tensioner'. does the D3 normally come with one and you have removed it and gone to manually tensioning the belt? If so is it a better idea to manually tension the belt because of a serviceability issue with auto tensioners generally?

[TerryO]

Just had a call from the workshop that is fitting the bull bar and a few other goodies to the D3, I asked him to have a look for the noise.

Time will tell if he has got it right when I get the Disco back tomorrow but he went right through it and found a lose exhaust heat shield that is just behind the passenger side front wheel which was vibrating. He has pop rivetted it back to its mount but has not had a chance to drive the car yet as it is still in pieces.

Anyway thought it was worth a mention so others with the noise could have a quick check and see if their heat shields have come lose as well.

cheers,
Terry

[rdenyer]

My 2005 D3 TDV6 makes a similar noise under these conditions, much more noticeable when driving on a freeway next to solid concrete walls.
Not Engine related as I had a new engine 12 months ago.
Unable to re-create noise when car is stationary.
Dealer can't find anything

Regards,
Richard

[TerryO]

At my last service I had two serpentine belt pulleys / tensioners replaced and the noise went 95% away for about 300 km or so, then it slowly came back and now bout 1,000 km later it is back to how it was.

The belt was replaced 20,000 km ago by the way and the noise was there before and after it was replaced.


cheers,
Terry