T6.1. Cold engine noise

[Paul1]

Having had two T5s Ocean diesels I can’t recall having this noise. T6.1 first start up when cold when lightly accelerating away I hear rattling sound like timing chain noise when engine is under load. Approximately 20 minutes later when temperature is up the noise goes and engine sounds normal without the annoying rattle. 5500 miles , done it from new. Due 2nd service next month and shall bring the subject up with dealer but by the time I arrive there the noise won’t be apparent and even leaving it there overnight just reving the engine does not produce the noise, it need a road test. Is this normal for The T6.1 and nothing to worry about, anyone else experiencing this ? Forgot to say, after first start and engine warmed up noise goes even multiple starts from cold during the day and only reoccurring next morning when oil has settled all night?

 

[Stargazing]

Is this something you have noticed since owning it or has it been more noticeable over the last few weeks if colder where you are? Is it more under strain such as hills etc?
Diesel engines run slightly louder when cold until pressure builds, but any persistent loud metallic noise would need a check out.
Its due an oil change, so maybe check the level before it goes in as VW can be shall we say 'a little economical' with oil. Check the level after service too.
I did read that new engines can experience a noisier diesel pump until bedded in, but someone might know more about that topic.

 

[sidepod]

Manual or DSG?

 

[Paul1]

Manual or DSG?

Ocean DSG.

 

[Paul1]

Is this something you have noticed since owning it or has it been more noticeable over the last few weeks if colder where you are? Is it more under strain such as hills etc?
Diesel engines run slightly louder when cold until pressure builds, but any persistent loud metallic noise would need a check out.
Its due an oil change, so maybe check the level before it goes in as VW can be shall we say 'a little economical' with oil. Check the level after service too.
I did read that new engines can experience a noisier diesel pump until bedded in, but someone might know more about that topic.

From new. Live in flat Essex. Next service will be 3rd oil change .

 

[sidepod]

Next to impossible to diagnose from a description.
Are you certain it’s load dependent? Can you knock it into neutral and coast? Try to determine if it’s engine or tranny?

 

[Perfectos]

Could be the belt tensioner , known issue.

Standing at the front of the vehicle looking into the engine bay the timing belt & serpentine belts are located on the left side of the engine block , covered by a plastic cover.


Video it on your phone !

Classic failure is rattling on start up and for a period of time after start up, then it goes.


Not wanting to be too alarmist but Failures can cause catastrophic engine damage due to the timing belt being destroyed. On t6 they modified the timing belt cover guards to help prevent catastrophic damage to the timing belt.



Get the dealer to check at service or take it to a local mechanic to diagnose.

Get the timing belt visually checked and have a new serpentine belt fitted at the same time as the tensioner (you will have to pay for a new belt , vw will not routinely replace it unless it is obviously damaged).

 

[Paul1]

Next to impossible to diagnose from a description.
Are you certain it’s load dependent? Can you knock it into neutral and coast? Try to determine if it’s engine or tranny?

Definitely engine

 

[Paul1]

Could be the belt tensioner , know issue.

Standing at the front of the vehicle looking into the engine bay the timing belt & serpentine belts are located on the side of the engine block , covered by a plastic cover.


Video it on your phone !

Classic failure is rattling on start up and for a period of time after start up, then it goes.


Not wanting to be too alarmist but Failures can cause catastrophic engine damage due to the timing belt being destroyed. On t6 they modified the timing belt cover guards to help prevent catastrophic damage to the timing belt.



Get the dealer to check at service or take it to a local mechanic to diagnose.

Get the timing belt visually checked and have a new serpentine belt fitted at the same time as the tensioner (you will have to pay for a new belt , vw will not routinely replace it unless it is obviously damaged).

Thank you, it’s booked in January. Armed with the above shall ask for an inspection.

 

[Perfectos]

Thank you, it’s booked in January. Armed with the above shall ask for an inspection.

Report back to help others pls

 

[Perfectos]

Here's a thread from t6 forum with an example

Cam & Aux Belt Tensioner Noise, Recorded.

So it's been widely reported that VW are aware of an issue with certain year/vin number Transporters that are developing noisy tensioners. I noticed a while ago that mine was starting to sound a bit noisy on start up when cold, but the noise would slowly disappear as the engine warmed up. The...

www.t6forum.com

 

[sidepod]

All of those issues are T6 are they not? OP has 6.1?

 

[Perfectos]

All of those issues are T6 are they not? OP has 6.1?

The op has a T6.1 with issues that sound like a failing belt tensioner, Applies to T5 onwards.

T6.1 has a belt tensioner which has the ability to fail?

My very brief google search turned up a thread with a video of the noise, which may well be helpful to the op in identifying if the issue they have is similar!

 

[Paul1]

Mine does not make the noise at tickover and i am reluctant to rev it when cold. The rattle comes when engine is under load when normal driving. Brought service and investigation forward to 22nd this month and they are keeping it overnight. Service manager seems to concur cambelt issues. It drives and sounds perfectly after approx 20 minutes and stoping and starting rest of day. Garage says no immediate danger .

 

[sidepod]

All very confusing. The noise/issues discussed above are related to the serpentine belt tensioner. Nothing to do with the cam belt.

 

[Stargazing]

Thank you, it’s booked in January. Armed with the above shall ask for an inspection.

Are VW charging a diagnostic fee first?

 

[soldana]

Don't know if this helps, but I had an issue with the auxiliary belt tensioner on my T6 (fixed under all-in warranty) - I would describe it as much more of a high pitched squealing noise than a rattling.

 

[Paul1]

All very confusing. The noise/issues discussed above are related to the serpentine belt tensioner. Nothing to do with the cam belt.

Sorry, cam belt was my mistake, he didn’t say that. He said it might be a slipping belt let them investigate first.

 

[Paul1]

Are VW charging a diagnostic fee first?

They are providing a loan van and no mention of fees. I expect and shall argue strongly that 6000 miles, under tow years old will be under warrenty.

 

[Paul1]

Cali went I for service and investigation yesterday. They wanted to keep it overnight so to road test first thing in the morning. Provided fully electric transporter as loan vehicle. ( yuck ) Call from them this morning and conclusion was, no fault, everything is fine. Perhaps I’m too sensitive. When I asked if they tested it as I asked ie stop and start . Light throttle, don’t just drive straight down dual carriageway ( A12). He Said , he didn’t drive it the engineer did and the service might have cured it. I said I’m doubtful if an oil change would cure they sort of fault if there was one. So, for now I will have to accept that and see if it’s gone next first cold start. . There was no charge for loan vehicle. Anyway it’s now on record. If it develops into something serious they won’t be able say it’s my fault for not reporting earlier..

 

[Stargazing]

Thanks for the update - always useful for others. Let us know comparison to next cold start from your perspective. Was the aux belt checked?

 

[Paul1]

Thanks for the update - always useful for others. Let us know comparison to next cold start from your perspective. Was the aux belt checked?

I can see and felt the main belt , it looks fine and dry and tensioned. I don’t know what the aux belt is but they were fully aware of my concern before they done the service and I would hope they carried out some basic checks. As nothing was heard or amiss they would have charged for a thorough investigation then finding nothing wrong. Now it’s been checked and if it’s still the same I will live with it. It lasts for 10-15 mins and only can be heard if the radio or heater blower isn’t on.