[Mégane III] Loud engine -P0 :: Planète Renault

[Mégane III] Loud engine

Planète Renault Index du Forum > Technique [Mécanique]

ReDRuM
Nouveau

Inscrit le: 08 Juil 2012
Messages: 3

Dim 08 Juil, 2012 17:11:35

Hi guys, sorry for writing in English, but I'm from Croatia and I thought that someone here might me able to help

My problem is:

I bought a used 2009 Megane Coupe 1.6 16V a couple months ago and the only thing that's bothering me is the loud engine. The guy in the local Renault dealership told me that the sound is normal but I'm not that sure.

The engine gets really loud in the 3500 - 3900 rpm range while driving. Above and below this range the level is acceptable, so I'm guessing it's some type of resonance. I would describe the sound as normal engine sound only loud.

For the geeks -> The sound is fairly low in frequency -> Around 150 - 200 Hz.

It would be quite weird that this is normal because everyone notices that my car is loud, i.e., I'm not imagining things

Is this normal or can it be "fixed"?

Thanks a lot!

Dernière édition par Transam le Dim 08 Juil, 2012 19:47:15; édité 1 fois

Bib30600
Losange de cuir

Inscrit le: 12 Aoû 2009
Messages: 745
Localisation: vauvert

Dim 08 Juil, 2012 19:49:43

salut

peut etre un support
maintenant reste a savoir lequel (moteur / bv / couple)

rpm91
Losange d' Argent

Inscrit le: 30 Juil 2008
Messages: 6723
Localisation: Pôle Nord (de l’Essonne)

Lun 09 Juil, 2012 08:24:20

Hi ReDRuM and welcome

it's rather normal to get a resonance at this engine speed range on petrol engines

At 3900 rpm, the frequency emitted by engine combustion is 3900 * 2 /60 = 130 hz
Have you measured the 150 hz or, just estimated?

I also notice a noise increase on my own Laguna at 4000 rpm, even it's equpped with a flexible flywheel, which is aimed to reduce this kind of resonance noise.

_________________
Ma Laguna II.2 2.0 16V BVM Estate Confort Dynamique 2007 - Attelage - Tom-tom GO930T - 51 500 km - 8,8l/100
Honda SH300i 2011 - 12 200 km - iMac 20" :mrgreen:

Enfant, je rêvais de sauver des vies, aujourd'hui, je le fais

ReDRuM
Nouveau

Inscrit le: 08 Juil 2012
Messages: 3

Lun 09 Juil, 2012 13:27:59

Thanks a lot for answering.

Yes, I estimated the frequency. I measured it today with an RTA and you are correct.

What I find weird is that it's noticeably louder within this one rpm range (cca 3600 - 3900)...

Can this be "fixed" somehow? I heard that Renault used to install some kind of soundproofing material under the front hood of the car, and that you can still buy it as an option. Do you think this would help?

To me it seems that the vibration/sound is transferred through the chassis itself and I'm not sure if the soundproofing material under the hood would help much.

Thanks.

rpm91
Losange d' Argent

Inscrit le: 30 Juil 2008
Messages: 6723
Localisation: Pôle Nord (de l’Essonne)

Lun 09 Juil, 2012 16:17:53

I also guess that no soundproof material can efficiently reduce this kind of noise

_________________
Ma Laguna II.2 2.0 16V BVM Estate Confort Dynamique 2007 - Attelage - Tom-tom GO930T - 51 500 km - 8,8l/100
Honda SH300i 2011 - 12 200 km - iMac 20" :mrgreen:

Enfant, je rêvais de sauver des vies, aujourd'hui, je le fais

nicov
Losange de cuir

Inscrit le: 18 Juin 2004
Messages: 678
Localisation: 48°77N 2°E

Lun 09 Juil, 2012 16:38:32

You may want to check the quality of the silent block(s) holding the engine, as advised by Bib30600
But in my case, the vibrations transferred to the chassis were max at idle RPM (about 750rpm) due to degraded silent block.

ReDRuM
Nouveau

Inscrit le: 08 Juil 2012
Messages: 3

Mar 10 Juil, 2012 11:35:02

Hm... But do you think this could be normal? That the engine is noticeably quieter at slightly higher rpm?

Dernière édition par ReDRuM le Mar 10 Juil, 2012 11:35:25; édité 1 fois

Planète Renault Index du Forum -> Technique [Mécanique]

Toutes les heures sont au format Array

Sauter vers: