blown turbo noise?

[RoadRage]

So I replaced my DV tonight and while I was doing that I noticed a decent amount of oil in the old DV, and PCV valve (I was checking for boost leaks). Is this a sign of a dieing turbo?

Also, after the car is revved above about 2500 rpm and I let off the throttle, I hear a loud drill type noise. Is this the blown turbo dentist drill noise? I'm not sure if the blown turbo noise happens while you're pushing on the gas pedal, or after you take your foot off the gas pedal.

Someone care to clarify? I can post video of the sounds if needed.

thanks.

[CELison]

A blown turbo "dentist drill whine" will be heard under boost, not when getting off the throttle. when you let off the throttle you will go into vaccum right away. Go in 2nd or 3rd gear and put your foot down. If you have a blown turbo you will know it. When my k03s blew there was no question about it. Its not a light whistle its a loud whine. As for the oil, a little bit is normal.

[danphines]

http://www.youtube.com/watch?v=XSEFU...eature=related

[RoadRage]

Ok, so my turbo is definitely not making that noise. But when I let off the throttle it makes a noise similar to that, but a much deeper tone. I guess I'll just post up a video tonight after work.

[danphines]

my guess from the fantastic description you provided would be boost leak or vacuum leak

[RoadRage]

Yeah pretty vague huh?

Ok, here's a couple videos of the noise. It's hard to hear it in these videos, but if you listen closely after I let off the throttle you can hear the noise kick in.
And actually after listening to these videos, it sounds like I might have some other issues.


sorry about the door chime.

[CrtchRktRcr]

i don't hear the noise...revving the shit out of your car while it's cold like that isn't going to help. Cars always sound a little different when they aren't warmed up

[RoadRage]

That is very true, I probably shouldn't rev it cold.

But, in that second video you can hear the noise in the beginning right as the needle comes down to 2k.

[EuRo_KiD]

This might be a dumb question, but will a blown turbo even hold boost?

[RoadRage]

^ I have no idea. I think it will produce a little boost.

I need a boost gauge. Anyone have one available for cheap?

[CrtchRktRcr]

Go to checker. 25 bucks.

[marknad113]

the dentist drill noise on decel is most likely your wastegate flapping. thats exactly what happened to mine, and a ton of other A4s. there is not really a good fix for it, if you search there are some threads on it

[RoadRage]

the dentist drill noise on decel is most likely your wastegate flapping. thats exactly what happened to mine, and a ton of other A4s. there is not really a good fix for it, if you search there are some threads on it

Thanks for the advice, that was the next part I was going to look into. So, if the wastegate is flapping that basically means the turbo is crap right?

[walky_talky20]

No, sometimes you can just tighten up the adjustement on the arm, as long as everything is still there.

I hear the noise you are talking about. Kind of a raspy rattle when going into decel. For about the first 1,000 rpms of decel. Sounds to me like either a vacuum leak or a wastegate rattle. Also, my a4 made a [sort of] similar noise from the cam chain tensioner. More of a grinding, really. And more on accel than decel. Maybe not so similar...yeah.

Anyway, you should be able to locate the noise using a screwdriver with the handle in your ear and screwdriver end (?) touching various crap in and around the engine. You should be drive-by-cable so you can rev the engine with your hand from the engine bay. Or have your trained assistant do it for you from inside the car.

If you have vag-com, you can look at the fuel trims. That might give you an idea if you have a vacuum/boost leak. A boost leak test wouldn't be a bad idea either.

[RoadRage]

I'll probably do that after I get these damn control arms replaced....

I don't have vag-com, but I recently did a boost leak test and a melted check valve and a small leak in the hoses under the IM. Also, I don't know if this is normal during a boost leak test, but after pressurizing the system I can hear and feel, what I'm assuming is oil, dripping into the oil pan. I put my hand on the front of the pan and I could feel the liquid dripping in. Is that normal? I really hope that was only oil and not coolant or anything else.

[AudiB5owner]

Hey!!!

Did you ever figure out what this sound was?? I have a 2001.5 B5 A4 1.8t and it makes the SAME sound. When using a lower gear to go down a hill, it sounds horrible and the grinding sound is super loud. Only happens when my foot is off the gas and the car is reving moderately high ~2500 rpm. Any help please, I am lost and hoping my car isn't dying!

[Fly_R_Die]

My 2000 B5 A4 makes the exact same noise. When I popped the hood and had my brother rev the enginge a little bit it sounded like it was coming from the turbo. Good thing my Frankenturbo will be here tomorrow

[AudiB5owner]

Hey Fly R Die thanks for posting. I had my friend do the same but I couldn't diagnose the source, thought it was the engine or turbo. My turbo spools and all but still getting that damn grinding noise. What kind of turbo are you replacing it with? Eager to know if that is the solution!

[Fly_R_Die]

Im going to use the F21L from Frankenturbo. I sure as hell hope thats the solution for me lol but I was planning on replacing the turbo anyway

[EliA4B5]

If you are very careful while driving and not getting any sort of smoke out of the turbo or your exhaust you can still drive on it until you are able to afford your new turbo swap.
I have been driving on a rattling stock k03 turbo for 10,000 miles now
after driving for about 10 mins in very low rpms and when the oil pressure gets to it, it stops rattling and I can get a very tiny boost from 3000rpms to 3.5rpms lol
I have been saving for a Frankenturbo F21L myself. I am just worried that I will have to replace the clutch as soon as I have it done because its starting to slip (previous owner chipped it without any sort of supporting mods)

[jcr223]

It's a waste-gate rattle, I'm currently dealing with the same issue. I notice it on my 2.0T with 58k miles, now have 95,000 on the clock turbo still boosts to about 18 stage 1, but just started to throw an under-boost code.

Goodluck -- I've found no viable fix on this thread, and plan on replacing turbo at some point.

[AudiB5owner]

Well at 90,000 miles I just had the Power Steering Rack replaced along with the front axle and engine mounts, and also had them check out this sound that can be heard in the second video. Mechanic thinks it is a loose impeller rather than a waste gate. Regardless, if you are hearing this sound you probably should start up a rainy day fund for a new turbo! Sad to spend so much, but hey, an upgraded turbo would be great!

I don't think there is a fix other than getting a turbo swap.

&EliA4B5 : I have driven with this problem for around 15,000 miles now and haven't had turbo failure or have oil start to smoke out of control *Knock on Wood* Local APR mechanic wants $1000 for a BorgWarner K03 and $1500 for a K04 running on stock ECU with a boost controller for the K04. Time to start saving up

[disturbed_audi]

would this sound be classified as a fluttering sound on decal in boost? I just thought my dv or vac line to dv was garbage?
edit I did boost test. when you do your boost test does that also check your vac lines?

[AudiB5owner]

would this sound be classified as a fluttering sound on decal in boost? I just thought my dv or vac line to dv was garbage?
edit I did boost test. when you do your boost test does that also check your vac lines?

This is not a flutter sound, more like a grinding/loud fast ticking sound on decal related to the turbo. You may be hearing your DV fluttering upon decelerating, depending on where your boost gauge is connected to, it is usually tapped into your vacuum line with a T splitter, I'd check around the forum for some more info.

[ToXicXxX]

Well at 90,000 miles I just had the Power Steering Rack replaced along with the front axle and engine mounts, and also had them check out this sound that can be heard in the second video. Mechanic thinks it is a loose impeller rather than a waste gate. Regardless, if you are hearing this sound you probably should start up a rainy day fund for a new turbo! Sad to spend so much, but hey, an upgraded turbo would be great!

I don't think there is a fix other than getting a turbo swap.

&EliA4B5 : I have driven with this problem for around 15,000 miles now and haven't had turbo failure or have oil start to smoke out of control *Knock on Wood* Local APR mechanic wants $1000 for a BorgWarner K03 and $1500 for a K04 running on stock ECU with a boost controller for the K04. Time to start saving up

If you need a stock KO3 I just pulled one with 5000km on it... No shaft play, pretty much brand new.

[AudiB5owner]

If you need a stock KO3 I just pulled one with 5000km on it... No shaft play, pretty much brand new.

Hey thank you for the offer, I'll have to PM you in the future if I need one. I may just go ahead and upgrade the turbo but until then, I am just going to drive until it goes!

[Lucius.n]

http://www.youtube.com/watch?v=XSEFU...eature=related

Video is private. How can I view it otherwise?