Hi all,

 

Have just had my turbo replaced and the mechanic had picked up on a quiet, rubbing/chugging type sound coming from the N/S lower engine bay.  This noise has been present for at least the last 25K and I’ve never worried too much about it.  Although I have noticed at times, it is particularly loud (usually when the engines stone cold).

 

He’s told me its one of two things:

1)   Bottom end engine failure (or leading to that)

2)   Gearbox or DMF

 

I had the clutch & DMF replaced about 15-20K (Luk) ago and have noticed two things since having this work done:

1)   Lifting the clutch up in 1^st to set off results in quite a loud chatter

2)   The gearbox can sometimes make a real unpleasant chattering sound occasionally in neutral.  Putting it into gear and out again usually solves it

 

I have no idea if the clutch & DMF replacement could be the culprit or not, but I think this noise has been present prior to this work being carried out.

 

I’m taking it back for further inspection in a couple of weeks but wondered what thoughts anyone had on the noise?  It’s hard to make out under the general engine sound but I’d describe it as a stream train type chugging/rubbing sound.  Having had a look through posts talking of bottom end failure, the noise seems more pronounced with an obvious tapping.  This isn’t the sound here.

 

Service history is great.  Every 10K by Skoda with all receipts/invoices up until 110ish then privately at garages I trust or I've changed the oil and filter myself using Quantum 505.01 (and always supply this to garages too).

 

I do love this car but it doesn’t half empty my pockets!

 

Thanks!

 

(unable to upload to Briskoda so the audio has been uploaded to a 3rd party site)

 

http://vocaroo.com/i/s0TI06urLpAw

Edited 13 September, 201411 yr by Dave89

You can't hear alot tbh through the audio unfortunately mate. I've been a technician for 10 years and you know if an engine has a bottom end knock! I would take it to an expert if you believe their is a genuine issue. 

 

Listening to any gearbox/ dmf from underneath car sounds loud on a ramp specifically on older diesels. Mine sounds identical and has done for 4 years. 

 

Just make sure someone isn't miss diagnosing at you're expense mate.

 

Olly 

Not a chance it's bottom end failure, once the bottom end is damaged it fails quickly and noisily.

 

If it ain't broke...

i got a spare bottom end if needed pm me

Checked box oil?

If not drain and refill with fresh oil be surprised the difference it makes

it just sounds like a typical diesel to my ears, if anything were wrong it would have gone bang 25K miles ago. I really wouldn't worry about it and carry on enjoying the car.

Thanks all for the advice.

I'll try and get a clip when the noise is more noticeable as you can't really hear the rubbing chugging noise over the general engine noise.

It does drive fine so hopefully isn't anything serious. I've been told the sump can be whipped off to see if something's rubbing.

Before I'd even read to the end of your original post I read the word 'chugging' and immediately thought DMF. Mine sometimes sounds like a train! However, it's been like this for about 60k miles now, and it still refuses to die even with over 300ft/lbs!

Thanks alex_e3.

 

I discounted the DMF as it was replaced not so long ago but that might be normal for the Luk DMF that's gone on.  I'll keep my ears open and hope nothing comes of it!

 

 

2)   The gearbox can sometimes make a real unpleasant chattering sound occasionally in neutral.  Putting it into gear and out again usually solves it

 

 

 

 When in neutral, the gearbox input shaft can start to freewheel at engine speed, Depressing the clutch and selecting a gear stops this rotation as the input and output gears mesh. This could be what is happening. If you leave it for a few minutes with clutch pedal lifted after doing the above, does the noise return. If so, may be a gearbox bearing. The other thing is, if you just depress the clutch and lift it again without selecting a gear, does the rattle disappear as if it doesn't it would suggest a gearbox bearing.

Hi Keith.

It doesn't occur often so can't comment on what happens if I put it in gear, take it out and leave it a few minutes.

I do know that dipping the clutch makes no difference. Based on your post, that's the sign of a gearbox bearing? For future reference if it gets worse, is it a gearbox rebuild job or something less major?

Many thanks

Mine has a very slight chugging noise coming from around the aux belt area when cold but never thought anything of it. Just thought the belt might be getting worse for wear as the car was sat for around a year before I bought it

Deffo not the aux belt area. Sound is definitely lower down and had new alternator pulley tensioner and belt.

But.. I can see the noise not sounding too different

I'm thinking mine might not be aux belt now lol

Could be the belt. Tensioner and pulley can cause all sorts of sounds if they're on their way out.

My noise is very apparent from under the engine or from the NS wheel arch. If it's the alternator area I think this would be quite obvious to locate.

Could be the belt. Tensioner and pulley can cause all sorts of sounds if they're on their way out.

My noise is very apparent from under the engine or from the NS wheel arch. If it's the alternator area I think this would be quite obvious to locate.

 

Could be paranoia because you've just had your turbo replaced, it's traumatic I know, but if there's nowt wrong with the car then just drive it!

Had the noise for a while, and aware of it for the last 25K at least.

Perhaps I'm paranoid it's getting louder, it might not be.

Either way I'm not going to worry too much. Going to have another mechanic have a look for advice but as others have pointed out, it's been ok for those 25K miles!

Sounds like a dmf.

Could be completely unrelated but I've experienced a low rumbling noise at low rpm when maneuvering in car parks etc.

 

Turns out it was the gear linkage cables vibrating against a heat shield that covers the flexi section of exhaust, because of where the heat sheild is mounted it amplifies the sound.

 

It's easy to get to if this is the case and a cable tie around the cables has managed to cure mine for now, the heatshield mounts have failed though and occasionally sags down causing the vibration sound to come back. It is located at the back of the engine bay where the exhaust goes under the bulk head, the cables are insulated in something that resembles aluminium foil.