Passat 125kw TDI vibration and resonance at 1200rpm-1500rpm

[ST33VI]

you said when u put ur hand over the intake the noise goes, just trying to think of anything possible, but very hard to say without being there to hear the noise/vibration. maybe it would b worth letting an independant look at it, although it will cost.

[theshark]

I drove my 118TSI with engine rev 1200 RPM, speed 30 km/h several times today. The resonance didn't stop until engine rev up above 1400 RPM or below 1000 RPM. It would be very annoying if you are driving through a school zone during school hours. It's interesting no one in the Passat sub forum reported any resonance issue, and no much info found on google either.

[Greg Roles]

Perhaps ST33VI is indeed onto something....perhaps take the filter element out, see if it is any better or it changes revs. You'll need a torx set to get the lid off, you can get pocket knife style ones quite cheaply at Supercheap. The next step I would try is to disconnect and drive without the airbox hooked up, then try the box but without the intake loop to the front of the car ( it just clips together ), keep adding and removing parts till you work out if it is in the intake.

[TDI DSG]

I will try with and without that air deflector tomorrow.

While searching for info on this resonance problem I came across the following thread about a restrictor in the turbo inlet.....

Turbo Resonance Dampener Removal - TDIClub Forums

[theshark]

Could that be exhaust resonance?

[Greg Roles]

I will try with and without that air deflector tomorrow.

While searching for info on this resonance problem I came across the following thread about a restrictor in the turbo inlet.....

Turbo Resonance Dampener Removal - TDIClub Forums

I've messed with the turbo outlet in my GT, and all opening that up did was increase the turbo noise and you could hear the turbo like it was in your dash. That part does look WAY more restrictive than what I found in the MKV, but I ended up putting the stock 'muffler' back in as it was the same size as the housing outlet ( unlike that one ) but mainly because it was dramatically quieter.
See post 179 in my serious tinker thread in diesels.

[theshark]

I'm having this issue at the moment with a diesel similar to mebius9.
Please post up how you go with the dealer, as I have had no luck thus far. Have been told it's normal.
Some people (me) are more prone to picking up the annoying frequency than others.
A quick google shows it's not uncommon in diesels - not found any mention of it for the TSI though !

Copy and paste from the thread i started on Passat forum,

Update

Picked my wife's Passat back from dealer service dept. On Service Invoice, it shows "Resonance through vehicle at 1200 RPM. Road test vehicle for noise. Identified concern. Contacted VGA technical department in regards to issue. At this point and time it is not a known concern and no further action be taken as advised by VGA"

The mechanic was helpful and told me at least 15 complaints for the same issue from a single country is needed to for VAG to look into it.

I'd like to draw all MY11 Passat 118TSI owners' attention to check if your car has the same issue. Ours does, so does dealer's demo (brand new MY11) car.

The best way to test is driving through a 40km/h school zone during school hours, listening the resonance/noise/humming level while your tacho is at 1200 RPM.

Thanks in advance for your help.

[Transporter]

Copy and paste from the thread i started on Passat forum,

Update

Picked my wife's Passat back from dealer service dept. On Service Invoice, it shows "Resonance through vehicle at 1200 RPM. Road test vehicle for noise. Identified concern. Contacted VGA technical department in regards to issue. At this point and time it is not a known concern and no further action be taken as advised by VGA"

The mechanic was helpful and told me at least 15 complaints for the same issue from a single country is needed to for VAG to look into it.

I'd like to draw all MY11 Passat 118TSI owners' attention to check if your car has the same issue. Ours does, so does dealer's demo (brand new MY11) car.

The best way to test is driving through a 40km/h school zone during school hours, listening the resonance/noise/humming level while your tacho is at 1200 RPM.

Thanks in advance for your help.

Is this problem also in TDI Passats?

[TDI DSG]

Copy and paste from the thread i started on Passat forum,

Update

Picked my wife's Passat back from dealer service dept. On Service Invoice, it shows "Resonance through vehicle at 1200 RPM. Road test vehicle for noise. Identified concern. Contacted VGA technical department in regards to issue. At this point and time it is not a known concern and no further action be taken as advised by VGA"

The mechanic was helpful and told me at least 15 complaints for the same issue from a single country is needed to for VAG to look into it.

I'd like to draw all MY11 Passat 118TSI owners' attention to check if your car has the same issue. Ours does, so does dealer's demo (brand new MY11) car.

The best way to test is driving through a 40km/h school zone during school hours, listening the resonance/noise/humming level while your tacho is at 1200 RPM.

Thanks in advance for your help.

I have reported it at two dealers now. Mine is diesel.

First dealer was not the dealer we purchased from for the MK6 but was for the MK5. They have done all servicing on the MK5, and were allways going to get servicing for the MK6. They couldnt get the spec of MK6 at the time and were considerably dearer anyway.
First dealer looked into the vibe once and did aknowledge it - said to bring it back if I was not happy, so I did a few days later. Delt with dealer manager (I think - wasnt service manager as was allready dealling with him), he basically told me they all do it but we wont do anything about it as you did not buy it from us.

Second dealer was where we purchased. Spoke with service advisor who imediately said "I could not drive it like that - it would drive me crazy".
After a few days we received a letter in the mail saying they are all like this "normal for this model".

Currently deciding what to do next.
Dont really want to get rid off it, but its looking like the only solution !

[theshark]

Is this problem also in TDI Passats?

Not sure if you meant MY11 125TDI.

My B7 MY11 Passat 118TSI does it. Dealer's demo one does it. Mebius9's new Mk6 GTI does it and so did his 2008 Passat 125TDI (please see my thread in "Passat TSI Resonance While Engine Revs at 1200 RPM" in the Passat forum).

Now I hope the resonance will eventually go away after the exhaust builds up enough dirt and changes it's built-in frequency. A reader in myturbodiesel.com reported the resonance with his 2010 TDI Golf Wagon disappeared after a year with 11,000km on the clock. 2010 Golf Wagon TDI engine vibration. It'd be a painful year if I have to drive this car through a number of school zones in mornings.

I raised our concern in regards to the unpleasant resonance on VW Australia website more than 10 days ago. I have got nothing but an auto reply from their website so far. The customer service level is not impressive.

[TDI DSG]

The fact that another car on the lot has the same vibration does not mean it is normal - it just means it has a problem also !!

If it is present in both diesel and petrol models the one thing in common could be the DSG ?
Would it be a balance issue with the DMF ?
I can now produce the same vibe in neutral or park while stationary by slowly raisng the rpm to the problem range.
I doubt it is an exhaust resonance as it does not seem to be affected by throttle position/load.

I had an independant VW specialist look at ours. He said they all do it, but he felt ours was probably worse than normal.
He also indicated dealling with VW to get a resolution would be difficult at best.

[theshark]

...I can now produce the same vibe in neutral or park while stationary by slowly raisng the rpm to the problem range...

I tried the same before, leaving DSG at P or N while stationary. The unpleasant resonance level at 1200 RPM is the same as it is when DSG is left at Drive.

I tested with my own car, an non-VAG car, and found it has cabin resonance at 1000 RPM too, however the level's never reached an unpleasant or annoying level and it is much lower than our Passat TSI.

For me, it sounds like an known issue for a wide range of VAG cars as they tend to share the same parts. I think it was an individual or batch problem as some did say their Golf, Passat or Skoda were whisper quiet.

[TDI DSG]

I tried the same before, leaving DSG at P or N while stationary. The unpleasant resonance level at 1200 RPM is the same as it is when DSG is left at Drive.

I tested with my own car, an non-VAG car, and found it has cabin resonance at 1000 RPM too, however the level's never reached an unpleasant or annoying level and it is much lower than our Passat TSI.

For me, it sounds like an known issue for a wide range of VAG cars as they tend to share the same parts. I think it was an individual or batch problem as some did say their Golf, Passat or Skoda were whisper quiet.

The thing for me is that my MK5 does not have this resonance at all, nor do the other two VW's in the family - all diesel's, but not commonrail's.
The annoying thing for me is we have upgraded to the MK6 and gone backward in refinement.

[theshark]

Low-speed Unpleasant Droning / Humming noise

Found an interesting Volkswagen Service Training Self Study manual for "Noise, Vibration and Harshness".

I'm now 99% sure the issue with our Passat appears to be a "Low-speed Unpleasant Droning / Humming noise" as described on page 4,

"Low-speed droning is an example of a low frequency NVH concern that may have components not in the audible range. This condition exerts pressure on the driver's eardrum and can be extremely uncomfortable."

More on page 10 and 11 for Theory of Droning. Page 11 lists items that could be responsible for unpleasant droning.

Update as of June 17, 2011
========================
I got hold of VW Customer Service today. They will be getting in touch with dealer's service dept and request dealer's service dept to do another inspection for our Passat next week.

[TDI DSG]

Found an interesting Volkswagen Service Training Self Study manual for "Noise, Vibration and Harshness".

I'm now 99% sure the issue with our Passat appears to be a "Low-speed Unpleasant Droning / Humming noise" as described on page 4,

"Low-speed droning is an example of a low frequency NVH concern that may have components not in the audible range. This condition exerts pressure on the driver's eardrum and can be extremely uncomfortable."

More on page 10 and 11 for Theory of Droning. Page 11 lists items that could be responsible for unpleasant droning.

Per page 8, Theory of Resonance, all cars "have their natural frequencies and experience maximum response at the point of resonance."

So VW Australia's technical department could possibly reply dealer's service department in saying "resonance is not an known concern" if dealer's service dept didn't use the wording like "low-speed droning".

I will be calling some dealer's service depts and get their opinions next week.

Folks, I think we may consider raising our concern from a Health and Safety perspective to draw VW Australia's attention, rather than a simple noise issue.

Just had a quick read through that document - very interesting.
It is exactly what is going on with our wagon, some people can hear it but are not bothered by it, and others like me are driven crazy by it.
My ears "pop" while driving along at 75-80 klm/hr from the low frequency effect. It is right in the driving range most used, so it is hard to drive around it.