2.0L 103 TDI making odd whine while boosting

[domlebo70]

Hi guys (long time lurker here),

My 45000km '06 2.0L TDI with Superchips map, has developed a new noise. Picture this: Car is in D, and short shifting to 4th at like 50kph. I squeeze the throttle enough that I'm accelerating hard, but the DSG hasn't kicked down. It sounds fine before the turbo reaches boost, but as soon as it has, you can hear a VERY disting friction sound coming from the turbo.

The noise is over the top of the regular turbo-spooling sound. It occurs only at full boost if that makes sense. So pulling away I do not hear it until i'm properly accelerating. It's much easier to hear in a higher gear then usual at lower revs. So 5th gear at 60kph, squeeze throttle and it's a bearing whine.

It does not sound like a leak, but I'm not entirely sure what a leak might sound like to be honest. It sounds very mechanical, very metal-on-metal. Possible bearing of some kind?

The car was JUST serviced (last week at the dealer for 45000km service) and nothing wrong was found besides wheel alignment and wipers lol.

Any ideas? If you have a video or soundbyte of something similar, or of a specific problem (so I can rule it out as sounding unlike that) then please post it

Thanks, Dom

[Buller_Scott]

hey man im afraid i cant really help you, but are you getting any CEL's or limp mode? is there more than usual soot upon acceleration?

how is the car usually driven- driven hard frequently, or babied a lot of the time?

have you had your EGR cleaned out, if indeed the car is babied alot? i'd also have a look around to check if there are any boost/ intake pipes that may have unclipped or been disconnected.

but from what i've read, it might be a case of examining the turbo for impeller shaft play + variable vanes grinding around.... where are you located? you might have to hold out for a reply from the guys who know their stuff on here, or take it to a trusted VW mechanic to diagnose the issue.

good luck with it. hope it's not the turbo.

[Greg Roles]

Unclip the inlet prior to the turbo and have a good look with a decent torch and a small mirror. You may be getting impeller to housing contact. The "bearings" in these turbo's are oil film total loss, in that the shaft spins on a film of oil under pressure, so there should be no metal contact generally. It's normal for oil loss bearings to have some slop without oil pressure, but I wouldn't think you should be able to get the impeller to contact the housing. Still that would be odd to have happening once on boost, and the oil pressure should be keeping the shaft centred. Hmmm, hard to pinpoint really, I'd suggest taking the service guys at the local dealer for a lap, and get their opinion. Sooner rather than later.

[domlebo70]

Hi Greg and Buller,

No CEL's, no limp mode. Car seems to have lost a tiny bit of power (perhaps 10hp :S - hard to tell, I am just estimating).

The car is driven very hard most of the time. I always let it warm up before thrashing it, and it's driven sedately to cool it down afterwards.

I will look around the engine bay for any piping that's been worked loose, however I'm not a very good mechanic, and I'm not entirely sure where the turbo piping is.

Turbo vanes being the issue would make sense, since my understanding is they are moved using a servo to vary the aspect ratio. That would explain why it happens at certain loadings, and not all the time, wouldn't it?

Who should I get to look at it in Brisbane? Or just take a peek in the "Recommended servicers" forum? I really hope it's not the turbo...

[Buller_Scott]

hey mate, as greg and the other oiler boys know, IIIIII am no mechanic by any means, but i just bit the bullet and started to try to get my hands dirty- first job was cleaning out the pipes/ intercooler.

if i can do it, anyone can, so pop the engine cover off [it's usually held on by little rubber knobs thatthe plastic engine cover literally ''pops'' up off, which will give you access to your engine bay.

the pipework will lead from the air box [air filter] down behind the back of the engine to the turbo, then down to the intercooler out front. you'll have to have a torch and have a little look see in the nooks and crannies, but the pipework is plastic/ rubber, with metal clamp rings fixing them together.

see what you can find, but if it's impeller grinding related, you'll have to go to someone quick smart like greg said. pm ''jmac'' on this forum- he's a very very very trusted vag mechanic in the brissy area, he should be able to help you out. but i would also check the recommended repairers in that section to find something reputable that's close to home.

good luck

[Greg Roles]

Get it to VW, or come over my place on the weekend. I'm in Ferny Grove, northside. I have some idea of TDI's : )

[Deeceer]

like Scott said, contact jmac (Jimmy) - he's been helping me out this last week and he's the real deal. Mobile too. And definitely sooner rather than later. I ignored a small sound 3 weeks ago and now I'm looking for a new engine...

[Buller_Scott]

that being said, greg is a tdi guru for sure, too.

if i lived in brissy i'd be over at greg's place all the time. even late at night without him knowing that i was there

[domlebo70]

Greg, what are you doing tomorrow? PM me if you're free. I have exams Thurs and Friday and it's booked in for fri.

[Greg Roles]

It's called "working" young fella. I remember those relaxed uni days....ahhhh....

Just get VW to have a gander, they'd have more experience in fault diagnosis than me, but yeah, I'm around on the weekend if you have no joy.

Just what I need, diesel stalkers!

[tonymaroney]

Mike Webber Prestige and Performance are pretty good too (Coorparoo). I have used Mike for some trouble shooting and have had positive results. My view is that the "independent" mechanics, and generally the ones that people have recommended, are much better at true "problem solving". If you want an oil change when the car in under warranty then go to VW, but I have never had good results with a true "difficult" problem getting solved by a car dealer mechanic. I've always had to get an independent to find the fault, or use the internet and copious hours of time. In some ways I think the independent mechanic relies on word of mouth, so they try harder, but also, even when they are stumped, their hourly rate or parts cost is normally less so they seem to get further into the solution.
For example...Mike Webber did a 60K service on my 06 2L TDI including DSG, as well as cleaned out and tested my air flow meter and tested the EGR flap, as well as a few other things (found the cause of a long term intermittent warning light that kept annoying me)...he did everything for $860, and VW wanted $1150 (I think..or more) for the service ALONE!
Have heard good things about Jmac too, but haven't used him personally.
Good luck!
Tony

[domlebo70]

It's booked in with these guys: Euro Aus Auto Mechanics - Volkswagon Service BMW, Audi & Mercedes Servicing and Repairs Brisbane & Redland

Have heard only good things from them, so hopefully they can shed osme light.

[gldgti]

if there is a vane sticking, its possible the turbo is trying to over boost and you can hear it surging. Surge is always seen at low revs, high load. The VNT is one of the best candidates for surge capability just because they spool so well.... Having said that, if you really have lost power then I would first call a boost leak. Boost leaks can sound like all kinds of different noises, depending on where they are coming from, how large they are, how close to the firewall it is, orientation, boost levels reached, etc etc etc. Also, boost leaks are common, especially among new diesels that run high boost pressures and that have intercoolers and lots of boost piping.

[domlebo70]

Stan (top bloke, top service) from Euro Aus mechanics took a look at the car this morning. Small oil leak from intercooler piping. Because he's unable to do warranty work he sent me to Austral. He thinks it's likely the vanes sticking.

[tonymaroney]

How did this pan out in the end? Did Austral have the same opinion of the problem and did they fix it up under warranty?