05 Jetta TDi BEW pumping noise from engine bay

https://vine.co/v/OUn5Br7q1Lz

Here is a short clip of the car running. It works perfectly but I get this pumping noise on start up and until it warms up. I'm wondering if there is anything in VCDS that could help narrow it down. The car has no CELs, no visible leaks, no misfires, stumbling or any other odd noises. It sounds like it's coming from the lower part of the passenger side engine bay and becomes very clear in the passenger wheel well.

Any helpful advice would be appreciated. Thanks!

Sure sounds like a bad freewheel clutch on the alternator................

The serp belt, tensioner and alt bearing was all replaced about 15k-20k ago. Isn't that something that wouldn't go away after warm? I remember when I replaced it, at least the tensioner, it making all kinds of noise whenever the car was on. And the alt bearing made more of a whine.

Timing belt tensioner 99%.
Take out drive belt and start car if you have same noise time for new timing belt job.

Jetta said:

Timing belt tensioner 99%.
Take out drive belt and start car if you have same noise time for new timing belt job.

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Isn't the service interval on the timing belt 100k? Something that I should do right away, or do I have a month or two? I'll try your tip out though. Thanks

04_sti said:

Isn't the service interval on the timing belt 100k? Something that I should do right away, or do I have a month or two? I'll try your tip out though. Thanks

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No, there was a TSB long time ago and reduce to 80k . This was done because there was so many cars with broken t/belt around 90k. After that MK5 with BRM came out with factory interval on 80k.
Same thing with CR2009+ , it says 120k and I found small roller and middle roller making noise at 100k , I suggest all TDi to do timing belt at 80k , or On CR 2009+, max 100k.

However there is a time interval of maximum 5 years, So if you have 60k on t/belt and 5 years old you need to change it.

But there is always can be that part can fail before this interval which is case in your situation.

You want to fix this right a way to avoid tensioner lock up and make damage $4000-$5000.

Jetta said:

No, there was a TSB long time ago and reduce to 80k . This was done because there was so many cars with broken t/belt around 90k. After that MK5 with BRM came out with factory interval on 80k.
Same thing with CR2009+ , it says 120k and I found small roller and middle roller making noise at 100k , I suggest all TDi to do timing belt at 80k , or On CR 2009+, max 100k.

However there is a time interval of maximum 5 years, So if you have 60k on t/belt and 5 years old you need to change it.

But there is always can be that part can fail before this interval which is case in your situation.

You want to fix this right a way to avoid tensioner lock up and make damage $4000-$5000.

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Ok. I have all the parts to do it, but was gonna wait until the spring time to do it. Guess ill be doing it early. And the car has roughly 80k on it since the last tbelt was performed. Which was by the dealer at around 100k. So its pretty much right on for being due for service. Just changed the front pads and rotors and wanted to find that noise. Looks like i found it lol.

Marin is correct.
You may want to check the freewheel first just to verify it.
It can make that noise due to a weak battery being recovered cold.

The timing belt/tensioner should be done.

Jack@European_Parts said:

Marin is correct.
You may want to check the freewheel first just to verify it.
It can make that noise due to a weak battery being recovered cold.

The timing belt/tensioner should be done.

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Jack I know this noise , I heard it to many times, it is not flywheel 100%.

I agree it is not flywheel......... That is usually a very different noise.

I am saying it can be the freewheel pulley on alternator sticking.
The same noise can be exhibited when someone puts a solid pulley on the alternator.
The wrong length belt can do this, as can a weak spring in tensioner of serpentine.

You are also correct that it can be the timing belt tensioner but usually this does this at all temps.

That is why I agree he should remove the serpentine belt and see if noise is vacated, and if so........ feel each pulley for true silent function of bearings and spin check the free wheel.

****UPDATE****

Performed the timing belt service this past weekend. Thought i had the wrong belt size at first but it was the correct one. Noise is gone and everything is working correctly. Followed the guide from tdiclub and everything turned out perfectly. I bought everything from IDparts, who by the way has great prices and all the parts youll need to work on your diesel if you dont know about them. Not sure if the noise was from the roller or the tensioner. The roller had a lot of play from the bearing and the tensioner not as much. Either way, noise is gone.

A lot of people seemed to complain about getting the mount out of the way but i didnt have much of a problem with that. I went with the engine support from the top. Just make sure you put the belt into place along with the mount at the same time. Then put the roller and tensioner in place. Make sure you put the bolts in the mount too before hand. Also, be prepared to put new bolts in. Just buy the bolt kit if yo do the TB. I stripped two harmonic balancer bolts and was in a bind so i had to use two bolts i had laying around from my EGR removal. They were 40mm in length rather than 37mm. No biggie. All in all it wasnt a bad install. Took me about 10 hours to do with breaks and shoveling snow and cleaning parts as i went along.

Thanks for the advice guys. The old belt was definitely showing its age for sure.

I see you got a metal water pump impeller instead of composite. whats the pros and cons of that?

Yea i didnt know there were 2 different versions until i took out the old one and it was composite. The composite being a factory item i suppose? The last timing belt job was done by the dealer. Idparts sells this HEPU part made in Germany. Seemed like a quality piece. Ive only seen metal impellers on cars before so this is the first time ive come across a plastic impeller. Not sure why VW has a plastic one.

04_sti said:

Not sure why VW has a plastic one.

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'Cause it's the cheapest way to make something that met their requirements?

Weak sauce.

Uwe said:

'Cause it's the cheapest way to make something that met their requirements?

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It call Techno-polymer impeller.
Actually it is made for better coolant flow . Since first Metal impeller was really cast and heavy , could not make very good flow , they want with Techno-polymer impeller.
But over the years OEM company's made it perfect , as you can see in picture above, very light metal material. .Some of them use Brass.

I remember I had one Audi A4 1.8 T ,about 7-8 years ago ,Where did not have heater . Problem was low quality metal pump . Pump could not make good flow and heater was working about 30%. At that time Pump with good metal impeller was on back order so I use in this car original Pump ( I had no choice) and heat cam back right a way.
Everyone was telling this guy it is heater core , But I was sure is pump because I look at VCDS coolant temp, and car was running little hatter then suppose to be. This is a thing with VAG cars , gauge will stay at 190 , but actual temp can be 210.

Jetta said:

I remember I had one Audi A4 1.8 T ,about 7-8 years ago ,Where did not have heater . Problem was low quality metal pump.

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Was the metal primarily chinesium?

04_sti said:

****UPDATE****

Performed the timing belt service this past weekend. Thought i had the wrong belt size at first but it was the correct one. Noise is gone and everything is working correctly. Followed the guide from tdiclub and everything turned out perfectly. I bought everything from IDparts, who by the way has great prices and all the parts youll need to work on your diesel if you dont know about them. Not sure if the noise was from the roller or the tensioner. The roller had a lot of play from the bearing and the tensioner not as much. Either way, noise is gone.

A lot of people seemed to complain about getting the mount out of the way but i didnt have much of a problem with that. I went with the engine support from the top. Just make sure you put the belt into place along with the mount at the same time. Then put the roller and tensioner in place. Make sure you put the bolts in the mount too before hand. Also, be prepared to put new bolts in. Just buy the bolt kit if yo do the TB. I stripped two harmonic balancer bolts and was in a bind so i had to use two bolts i had laying around from my EGR removal. They were 40mm in length rather than 37mm. No biggie. All in all it wasnt a bad install. Took me about 10 hours to do with breaks and shoveling snow and cleaning parts as i went along.

Thanks for the advice guys. The old belt was definitely showing its age for sure.

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I am glad I was able to help you.

Jack@European_Parts said:

Sure sounds like a bad freewheel clutch on the alternator................

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JACK
I won this time

Uwe said:

Was the metal primarily chinesium?

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Most likely ,casting was really low quality and you could see form pump it was very cheap pump.
He had some shop install this, not me.

Thanks again sir. Now its onto the front wheel bearings....yay.