2006 BRM weird noise from engine bay

[relumalutan]

My beloved Jetta started to make a weird noise last night. It's hard to describe, that's why I've made a video for you guys to watch in order to advise me.
It's a sort of a whistling noise, doesn't matter if the car is in park, neutral of drive. I've changed the DMF, so I doubt is that (it doesn't sound near close to the grinding noise associated to a failing DMF), I doubt is the EGR cooler (I watched some videos with the "hissing" noise). The noise is still there for 1-2 seconds after I turn off the engine. Any advise is welcomed, thank you in advance.
Link below:
https://www.youtube.com/watch?v=RIRIGvZLnIU

 

[nord]

Best to check the EGR cooler all the same. Belly pan off, on a lift, or SAFELY on blocks. The only thing is that charge air pressure really shouldn't remain for seconds after shutdown. For a few instants maybe, but not longer. So I agree that this is probably not the problem.

This leaves your turbo. It will spin down fairly quickly, but the turbo is the only part still turning after the engine shuts down. If I were to guess I'd tend to go in this direction. It would appear that this is a fairly new noise and that you're becoming more and more aware of it.

It might be of profit to remove the charge air tube at the bottom of the Intercooler and see how much oil is in residence. More than a few teaspoons is cause for concern. I'd also suggest inspecting the turbo for shaft slop and evidence of fin damage. (I have a bad feeling that you'll find both.)

 

[relumalutan]

Thank you Nord for taking the time to explain me in detail what is going on. I also tend to believe there is something wrong with the turbo. Worst case scenario, I'll buy a new one, maybe I'll find a DIY somewhere on how to replace it.

 

[dzldawg]

Sounds like Nord is probably right, but I had a noise kinda like that and it turned out to be the radiator fan slightly rubbing the AC connection line.

 

[nord]

Fans are something I hadn't thought of. A great idea and one worth checking out. And it can be done from top down!

 

[oceanrunner]

Subscribed

 

[relumalutan]

It's not the radiator fan(s). I've checked on that before posting. The weird thing is that now the noise seems to be going away. In the morning on my way to work I could hear it from the cabin at 70 mph, tonight on my way home I couldn't hear it at all. Parked the car in the garage with the engine running, the noise is not there anymore. At this point I don't know if it's a good thing or bad thing.... I'll keep an eye on it for the next days and let you guys know.

 

[nord]

At minimum check the lower Intercooler hose for excess oil. This, at least, will hint of a failing turbo.

If I'm correct and your turbo is failing, then you're dealing with a potential disaster. Waiting for the "bomb" to drop isn't a good plan. Should the turbo bearings be developing excess play, then it's possible for the vanes to have lost a bit of metal. Perhaps enough to reduce any associated whine.

All the same this doesn't make things better and your Dub is going to force the issue at some point if you don't get there first. Best to be proactive before the turbo loses its feathers and tosses chunks of metal into the intake and/or exhaust systems.

 

[relumalutan]

Nord,

I'm not a pro, but I'll try my best to in order to avoid a disaster. Please tell me what are my options in case the turbo is on its way out. There is such a thing as turbo rebuilt kit?
I've seen the Garrett PD140 turbo from the euro model for sale on IDparts. Do you think is a good idea to upgrade to it? Will that require an upgrade of the injectors also? Any ideas of the average cost of labor by an trusted mechanic to perform the removal and replacement?
I apologize for the ton of questions, any input is appreciated.
Thank you!

 

[nord]

Others will probably chime in here...

I believe there are available packages to rebuild your turbo. "Upgrades" I don't really get into. To rebuild or replace is a personal decision. I'd weigh costs vs. benefits and do what you think is best financially and for your piece of mind in the future.

If you go with an upgrade, then speak with the folks at IDParts. Good people!

Labor? We do all our own work, so I really can't be much of a judge. I can say, though, that cheapest may not be the best. On the other hand neither may the most expensive.

Find one of the folks here who are local to you and have a good reputation. They have skin in the TDI game and have every reason to maintain their their good name.

Before you jump please have a look inside your lower Intercooler pipe and see how much oil has collected. You might also profit (if able) to inspect the turbo impeller shaft for any play. It's best to know rather than guess.

Best of luck. I wish you were a bit closer as I'd be glad to help you.

 

[relumalutan]

Nord,

Thank you very much for your help!

 

[cevans]

relumalutan,

Does this noise change with RPMs? Have someone in the car rev the motor slightly to see if it changes.

Does the noise change with load? Drive with the windows down, find a big long steep hill and go up that hill with the car in a high gear and low RPM, doing 30 mph in 4th up the hill would work. This scenario will have the turbo at full-boost.

The BRM motor has an EGR cooler that is prone to leaking. If you look at the cooler you will see a vacuum line that connects to a small flapper valve. The shaft of this flapper valve can leak exhaust pressure, which results in a very high pitched noise.

PD140 turbos are AWESOME, but it can difficult getting it tuned right. If you are are a Jeremy Clarkson type (POWER!) then you'll love it, but if this is your daily driver and you aren't overly concerned about going as fast as possible you would be better served with a new OE/stock replacement.

 

[relumalutan]

As Nord says: "It's best to know rather than guess" so I will not waste your time with my guesses. I'll try my best to locate and identify the problem myself, if not I will contact a trusted mechanic.
The noise is back and it's present mostly when I'm stopped at lights. As the rpms go higher it seems to disappear. The turbo sounds normal under load, no changes in engine performance or fuel economy. I have VCDS, ran a scan, came back with no errors.
If I'll be able to pinpoint the problem, I'll try to solve it myself ( I've already changed the rear suspension, brake pads and rotors, and do all the regular maintenance with procedures I've learned from this forum).
First I'll check the intercooler for evidence of excessive oil leaks from the turbo.
I'll keep you guys updated.
Thank you again for your responses!

 

[MonsterTDI09]

I would check the turbo. Soon as possible.

 

[Spiked1Z]

If the noise happens only at stop lights and the car is pushing the correct about of boost, then I'm not sure how this would be turbo related... A lot of idle 'whines' are caused by worn serpentine belts, pully bearings or bad tensioners..

Also replacing seals in a turbo is rather easy once you have the turbo off the car. Though some bearing/races cannot be replaced, and for a proper 'rebuild/refresh' if the fan blades are in decent condition you would need to have the turbo shafts re-balanced.

If it happens when the car is stopped at idle pop the hood and try to listen where the sound is originating from. Stethoscopes work great for this.

 

[N.CaTDI]

I had a small exhaust leak before the turbo that caused a whine and would go away once a load was placed on the engine. This was where the EGR cooler attaches to the exhaust manifold. Hard to find unless you look up from the bottom and see black soot somewhere

 

[ro.sniper]

I also had an exhaust leak around my EGR plates... it didn't go away until I changed the warped plated. You might just need a gasket.

 

[benshaw]

that sounds like it could be the alternator pulley, take the v belt off and check it functions as it supposed to asap, as it will seize and brake off.

 

[poormanq45]

that sounds like it could be the alternator pulley, take the v belt off and check it functions as it supposed to asap, as it will seize and brake off.

This is exactly what I was thinking. It sounds similar to the dmf failure but on the opposite side.