This sound familiar to anyone? MkV Golf GTI 2005 (engine?) noise

[Fallout-NL]

It makes this undulating sound for a minute or two / three when cold. Goes away after that. And it seems like it really needs to sit for more than 12 hours for the noise to come back upon startup. If it's just a few hours since last firing it up, you don't hear it.

The cam/timing belt hasn't done much more than 10 or 20.000 km's.

The car has done 135.xxx km's.

Cam follower for the HPFP has been replaced.

Big service has been done recently.

It also makes this sound when the aircon is off. It seems to affected by engine speed.

Cam chain and tensioners haven't been replaced. My best guess is that those are the issue. Though perhaps one of you can instantly recognize what this is?

(Bonus question: what does that chain do anyway? Is that purely there to drive the fuel pump?)

My thanks in advance.

[mjmallia]

The typical cam chain noise to me is rattle ........try filming around the engine bay to see where the noise focus is, but cars with 80ish upwards start to require the change....mine was at 97k, my wifes at 90k etc.

The chain turns the two cams together and if it lets go due to the tensioner having given up......new head or engine depending on the speed you were doing at the time

[Fallout-NL]

The typical cam chain noise to me is rattle ........try filming around the engine bay to see where the noise focus is, but cars with 80ish upwards start to require the change....mine was at 97k, my wifes at 90k etc.

Thanks for your input! The 97k and 90k are in miles I take it?

I'll have another look with the hood up. See if I can narrow the sound down a bit. There is definite rattling when you increase engine speed, though not necessarily at idle.

The chain turns the two cams together and if it lets go due to the tensioner having given up......new head or engine depending on the speed you were doing at the time

Yes, fully aware of the bolded, haha. It's just that in most cases engines don't have both a belt and a chain right? That seemed a bit unusual to me. I'm fairly new to these engines, just bought this GTI in spring. Had a Boxster 986 before that.

[DBXdarkangel]

Does a 2005 have a chain? Mines a 2005 axx engine and assumed it doesn't have a chain.

[Fallout-NL]

I think it's like this: on the left side of the engine (if you stand in front of the car looking down into the engine bay) there is the 'main' timing belt that runs from the bottom of the engine to the cams. On the right side there is an additional chain, that serves to keep the camshafts in sync (and run the high pressure fuel pump).

So it has both?

On the MkVI's and up, the main belt has also been replaced by a chain if I understood correctly.

[pudding]

My first thought was dual mass flywheel, but it sounds more like a pulsating 'grinding' noise and not the usual rattling broken DMFs make. 

Noise travels around the engine compartment like an echo chamber, so you need to lift the hood and probe various components with a stethoscope.  Listen carefully around the chain cover area (your driver's side) on the engine and the gearbox.

Does a 2005 have a chain? Mines a 2005 axx engine and assumed it doesn't have a chain.

All MK5 GTIs have a chain.

The cambelt turns the exhaust cam.  The exhaust cam is connected to the inlet cam with a chain.  It's done that way for packaging as it makes a cambelt driven cylinder head more compact.  It's always been that way with VW's 16V engines (and the 1.8T).

The EA888 engine switched to chain only for less maintenance, but we all know how that turned out 

[DBXdarkangel]

I was told by a garage mine doesn't have a cam chain. Wasn't a dealer obviously just a local garage so assumed the early gti axx didn't have one. Might check the condition if mine then with vcds to make sure

[TomF]

I might be mistaken but I was of the understanding that the chain rattle only occurs when the engine is warm? I have had a similar noise on mine (2008 BWA, 141k), particularly cold starts in the winter, but had have no other ill effects and usually goes away within a minute or two. Definitely doesn't do it all the time, haven't figured out how to replicate it. So I'm definitely interested in any opinions on this as my chain and tensioner haven't been replaced either!

[Carpy25]

I had this sounded very like the chain

Old thread worth a read second post down

https://www.mk5golfgti.co.uk/forum/index.php/topic,101088.msg990181.html#msg990181

Rob

[Fallout-NL]

I had this sounded very like the chain

Old thread worth a read second post down

https://www.mk5golfgti.co.uk/forum/index.php/topic,101088.msg990181.html#msg990181

Rob

Thanks, that doesn't look great btw :D. Good thing you found that.

[Carpy25]

Mine sounded like the chain and I think some of the rattle was had the update kit fitted not cheap by the way a some noise still remained louder when hot got good vag train techs that look after my car they were still at VW at the time they tracked it down had to replace the whole balance shaft unit as parts were not available separately, had a good second hand unit fitted at 80k and car turned 150 k last week
Hope its not that but worth getting a  scope Mike on the area to listen

Rob

[pudding]

I might be mistaken but I was of the understanding that the chain rattle only occurs when the engine is warm? I have had a similar noise on mine (2008 BWA, 141k), particularly cold starts in the winter, but had have no other ill effects and usually goes away within a minute or two. Definitely doesn't do it all the time, haven't figured out how to replicate it. So I'm definitely interested in any opinions on this as my chain and tensioner haven't been replaced either!

Yeah a worn chain manifests itself as a diesel like chattering at a hot idle which doesn't go away when pressing the clutch down (or putting it in Drive on the DSG).  Turn the A/C off and roll the windows up.  Sounds like it's coming from behind the stereo.

You can perform a visual check by removing the vacuum pump (dead easy, 3 x T30 torx screws) and looking at how exposed the chain tensioner's piston is. Normally you can expect to see between 5-10mm exposed piston rod (depending where the engine is on it's firing order) but if you can see a lot of piston, the chain is worn out.  I'm talking 20mm+.

I.e. - this is normal



I don't want to be the harbinger of doom, but if the chain wear is ignored, this is what happens!  Notice what's missing!
 

[Fallout-NL]

Thanks for the additional replies. I will take all of it in consideration. Taking it to my mechanic in a week or two (and will leave it on the driveway until I go there).

Made two more video's with the hood up.

Engine cold:

Engine hot (for comparison, don't hear anything here really):

[LC5F]

Not really hearing much of a change except idle dropping from 1000 to 760 rpm when it warms up - its always there.

It does not sound like its coming from the chain - sounds more like its coming from the other end at the crank pulley.

Something rotating is not right, hopefully external to the engine that is easy to replace like a bearing in the alternator or drive belt tensioner.

[Fallout-NL]

Not really hearing much of a change except idle dropping from 1000 to 760 rpm when it warms up - its always there.

It does not sound like its coming from the chain - sounds more like its coming from the other end at the crank pulley.

Something rotating is not right, hopefully external to the engine that is easy to replace like a bearing in the alternator or drive belt tensioner.

I think you might be right. It does sound more pronounced when I move to the other side of the engine.

Like you said, hopefully external, haha.