New noise from '06 BRM

[goodmonkey]

A new noise appeared yesterday, and I have no idea what it could be. I'm hoping that some one might have heard it before and could help point me in the direction to help fix this. It seems high pitched, almost metal on metal. I recently change the oil with Liquid Moly 5w-40, and did some electrical work inside the passenger compartment. I replaced the CECM yesterday, and had the car ignition on for a long period without starting. I'm not certain if it was before or after that I noticed it. There are no trouble codes stored either, except airbag and radio (induced faults). Thanks for any help you can provide.

Video of the problem: https://www.youtube.com/watch?v=dxsWqbybGVs

My baseline video: https://www.youtube.com/watch?v=8OeYx5jpolo

 

[1998993C2S]

Man,,,, I'm at a loss. Possibly the HVAC circuit, say the A/C compressor? Possibly the A/C (pseudo clutch) pulley assembly is working or coming apart?

Great use of youtube . . . .

 

[GreenLantern_TDI]

Serpintine tensioner moving around alot. Alt pulley maybe starting to freeze up. Sounds like a bearing noise on the video. Pull serpintine belt off and run it. See if noise goes away.

 

[goodmonkey]

I've wondered about the A/C, as, well, it doesn't work great anyway. The noise doesn't change if the A/C is on or not.

Yes, the serpentine belt tensioner is bouncing a lot, and at idle I didn't think that was unusual. I tried to see if I could pick up on the vibration by touching my breaker bar to it, but didn't feel like that was it. I've had that thought, removing the belt to see if it goes away. Hope it doesn't fail on me, but if so, I guess that is what AAA is for.

The only point the noise almost disappears is when I'm decelerating, or the engine isn't producing any power. I would think that if it was a bearing that it would be all the time, but I agree that is what it sounds like.

Thanks for the input. I hope I can look at it this weekend.

 

[craig01b]

Pull the serp belt and see....I bet your ac clutch is toast.

 

[cobra390t]

Take the belt off and start it .. See if the noise go away , If it does , Then it's a process of elimination

Tensioner seems jumpy ( Alt pulley need to be checked )

AC compressor could be bad

 

[Kalter|Tod]

Pull the serp belt and see....I bet your ac clutch is toast.

These cars do not have an ac clutch. The pump is engaged all the time they use an RCV.

 

[goodmonkey]

Thanks. First COA is to remove belt and see if noise disappears. If it does, then I will start seeing if any item driven seems stiff, loose, or otherwise odd. It is the rather high pitched noise that seemed to suddenly start that has me baffled, but I will start going over it. I typically equate bearings going bad with a gradual roar or grinding, but maybe it really is the internals of the A/C compressor. I wonder if there was a leak somewhere if the refrigerant leaked out and took more PAG oil with it than it should. I still haven't looked into the A/C problem since buying the car, but I know the RCV is a likely culprit for that. It wouldn't be my first car with RCV problems.

 

[craig01b]

Still learning, I never really looked at it....regardless, belt off would still be my first action

 

[1998993C2S]

+1 .... No traditional A/C compressor clutch, hence the term used, "Possibly the pseudo A/C clutch coming apart?

The appearance of our A/C compressor's pulley is that of a clutch, but its no such thing. The actual (wide) belt pulley assembly is concentric to an inner hub and for the lack of a better term "riveted" together. This compressor pulley/nose assembly resembles that of a clutch ... however like Kalter|Tod points out.. there's no such thang .. clutch.

This pulley/nose assembly is known to come apart ...... Ask me how I know. Our TDI's initial symptom too was audible,,, as an ever-so-slight metallic noise - yet just below (db) the BRM's normal operating noise floor. The slight noise went on for a couple thousand miles until the pulley assembly (rivets) came loose jamming the rotation. The wide belt squealed, screamed and snapped while driving at 85mph just west of Vail, Colorado. Sidelined on Hwy I-70 with AAA Service a phone call away,,,, ultimately we drove the 10 miles to home in the village. (turn OFF all elective "electric" consumables as the electric power steering is operating on falling battery voltage)

A new OEM Sanden compressor fixed the TDI right up... this was summer '15 of last.

These cars do not have an ac clutch. The pump is engaged all the time they use an RCV.

 

[Ol'Rattler]

Pull the serp belt and see....I bet your ac clutch is toast.

I think you meant the alternator clutch is toast. It's great that so many folks will jump in and not bring anything of relevance to the table.

 

[GreenLantern_TDI]

I think you meant the alternator clutch is toast. It's great that so many folks will jump in and not bring anything of relevance to the table.

I brought alt pulley 8 posts ago. Not sure why its not relevant. Looks pretty relevant to me.

 

[goodmonkey]

Got to look at it in depth this morning. It is the A/C compressor. The alternator is okay too, no noise emitter when spun either ditection. Tensioner pulley also seemed okay. When I spun the compressor pulley, there was a metallic "tink" noise, like something is loose. There didn't seem to be much resistance. It looks like a new compressor is in my future. Thanks to all, here is a video of my findings:
https://youtu.be/tTU6zyxQAPs

 

[1998993C2S]

OP - The TDI's A/C compressor pulley (Sanden) removal could have been tight, yet accessible IIRC. Man,, a contortionist had nothing on me when attempting to snap a picture of the Sanden units part #, serial/type, etc.
That said, if our TDI's A/C pulley failure had not happened when it did, on vacation .... I'd have explored a pulley only R&R.

Is there an ETKA part number for the A/C pulley only? Maybe a donor pulley from a salvage yard Sanden unit? Sure beats opening up the A/C circuit if not truly required. "Why sail around the cape when you can replace only the pulley?" .... famous last words....

Add the failure of the A/C pulley to the list of Jetta MkV TDI 1.9 BRM service notables.. A shop tech at VW Denver went on to remark ... "We're seeing this compressor "rattle" more and more. Add this to the scare list created by the new car sales guy's... TDI owners trade-in on the spot .. at the thought...."

Got to look at it in depth this morning. It is the A/C compressor. The alternator is okay too, no noise emitter when spun either ditection. Tensioner pulley also seemed okay. When I spun the compressor pulley, there was a metallic "tink" noise, like something is loose. There didn't seem to be much resistance. It looks like a new compressor is in my future. Thanks to all, here is a video of my findings:
https://youtu.be/tTU6zyxQAPs

 

[goodmonkey]

It might be possible to replace just the pulley, if that indeed is what the root problem is, for the noise anyway. A quick search on Ebay results in something like this:
http://www.ebay.com/itm/NEW-AC-COMP...ash=item3aa32e3251:g:COkAAOSwZjJU~eyN&vxp=mtr

I don't have access to ETKA to check if that is really listed as a separate part number or not.

I agree, if I didn't need to open the system up I would be grateful, but I think there are other problems. I've never noted very good cooling since buying the car, but I've not looked into the reason much until now. I've noted that when the A/C is on, the compressor code in VCDS is 0, and from what I've found that should be full activation without any troubles noted. However, the coolant fans do not kick on. When trying to run the output test in VCDS for the fans (01 - Engine), I get an error stating that the controller doesn't control that function (actually, for all output tests with the ECU I get the same error). I'm not certain if these errors are because the ECU has a Malone tune or not.

So, my troubleshooting will continue, but I think yes, if the noise is indeed the pulley only, then it can be replaced. However, if I need to also replace the RCV, then I'm going to need to open the system anyway.

 

[1998993C2S]

Here's a tutorial from a firm ADPT ... speaks to the compressor type/tech in our TDI's..

https://www.youtube.com/watch?v=DPuYF0eNK6M

 

[1998993C2S]

Our TDI's A/C system, the dual "Climatronic" earns a "Best-minor" score on the Good, Better, Best scale. Fast forward 9.5 years & 177,000 miles, several Flap door R&R's, sun sensor and a compressor R&R by a clumsy tech whom needed 3 tries to get it right .... I can say the TDI's HVAC operation performance has slipped to only Good. Something ain't right?

My $.02 is the MkV chassis cars HVAC system is strong performer ... The non-climatronic and climatronic systems are dam near identical once past the climatronic's dual control aspect, etc.

FWITW, I've run with the Malone +1 since about age 5 / 55k miles. Never noticed any "tune" interaction and other sub-system with the VCDS. Good luck !!

Here is a link; HU 4663C for a replacement hub ala a Sanden unit at Polar Bear .com ... its a clue?
Several TDI Club folks have used Polar Bear for the RCV valve issue. All disclaimers apply .....
http://www.polarbearinc.com/PBPC/Homepage/products_Hubs.html#Anchor-SANDEN

 

[James & Son]

I don't think anybody has mentioned if the ac pulley(inner hub) is not turning it is because the pulley has a shear pin. this is to protect from ac lockup of compressor and resulting drive destruction. You have to do a search but I believe it is very difficult to see if the inner hub is turning. Most people have no choice but to replace compressor as it is usually toast.

 

[craig01b]

Wow, lots of blah blah blah for a little noise.....and I did mean to he ac compressor, not the alt clutch. The metallic nature of the noise sent me that way. I have replaced a couple on alh,s which failed. Wasn't aware they were different, mine is still working well on my 06.

 

[goodmonkey]

Update

When working to remove the radiator fans tonight, I took another look at this since I was under the car. The compressor hub does turn freely from the pulley, and when it does so I hear the clinking noise. I guess that means the shear pins have done their job and no more energy is being transferred to the compressor. Is that really how these work? And why would the hub spin without much any effort if the compressor was locked up, or is this just a failure of the pulley and hub?

I didn't look at it much, because getting the fans out to look at was my objective. It will take a little while to get through this, as I don't have a lot of time and have switched to driving the JSW for the time being.