Turbo Flutter......Help.

[schmiesus]

I'm not sure if its turbo flutter or surge. Under any accleration I can hear the "Boost sound" cutting out or "Fluttering". I did a search and people were saying that the DV torn or cause I have a Forge DV stuck open a little bit. I replaced it with a REV D. out of my other car to test it. Car is only peaking at 16PSI and was peaking at 21PSI before. I've done plugs, coilpacks, PCV & fixed a boost leak on the coupler that connects the breather tube to the valve cover (thinking for sure that was my preassure loss)

Nothing changed.

Wastegate? Tune? TURBO?

I'm trying to get a sound clip of the noise but all my phone picks up is my exhaust.

[schmiesus]

nobody?

[Charles.waite]

Could very well be the wastegate. Might have slipped out of adjustment.

[schmiesus]

good enough for me that's my weekend evening project lol

[ericpaulyoung]

If your DV is fluttering open, you will hear a little chirping sound like you have an angry chipmunk living in your engine compartment.

[schmiesus]

Definitely not that. Sounds like the boost is coming on and letting off then back on.

[ericpaulyoung]

it also sounds like a happy sugarglider (if you have every heard one).


http://www.youtube.com/watch?v=8LxAn0vIbrc

[schmiesus]

What have i witnessed here.


lol something like that yeah. I'm going to try and find some trees or something see if my phone can pick up the sound.

[jimrobbington]

Yeah, next step would be to adjust your wastegate. It's practically free. Tighten it a little bit, and you might be able to get it to hold again. Pretty much what happened to me back in the day, but I couldn't hear it.

[schmiesus]

I heard a rattle coming from down there on my way home at around 4psi so I think you're right

[jimrobbington]

I heard a rattle coming from down there on my way home at around 4psi so I think you're right

You have my DIY in the tech section for this, also.

[schmiesus]

I have it already preloaded on the garage laptop

[schmiesus]

I hit a snag before I did the work. Kinda glad I did too. I ran a boost log. This is 1st thru to 4th at WOT pulling onto the freeway. To me it looks like its getting what it's requesting so it's not out of adjustment? At least that's the way I am interpreting it.

I took a sound clip. sound clip (http://dubberz.com/uploads/exhaustnoise.wav)

http://dubberz.com/uploads/boost.jpg

[ericpaulyoung]

That doesn't look bad actually. Specified will drop out of range (so-to-say), when you lift off the throttle. In other words it will drop below the background noise (atmospheric pressure), so that the actual is sitting at something close to atmospheric and specified is down near zero.

- Eric

[schmiesus]

yeah so here is the background. The car boosted at about 21psi for about 3 weeks then one morning bam it's 15.

Its slowly been developing the noise in the sound clip aka what I've been calling a flutter.

I forgot to add this my Revo switched itself into stock mode last week randomly.

So am I driving myself nuts for a chip issue? The sound to me sounds like the car is over actuating wastegate maybe? I dunno.

[MedicCarter]

Prior to my DV going totally out I would get a sound at low RPMs in the morning. IT was like taking your hand and running it across metal window blinds not very harsh but I could hear it on my first turbo spool in the morning then never again. Then my DV failed and stuck open once I replaced it no sound and the car runs great don't know it that helps but your issue sounds like mine.

[ericpaulyoung]

Log the wastegate duty cycle. Put it in graph mode and drive around. When you hear the sound, look and see if it corresponds to a change in duty cycle.

And yes, the wastgate flapping open will definitely make chirping noises.

[schmiesus]

Prior to my DV going totally out I would get a sound at low RPMs in the morning. IT was like taking your hand and running it across metal window blinds not very harsh but I could hear it on my first turbo spool in the morning then never again. Then my DV failed and stuck open once I replaced it no sound and the car runs great don't know it that helps but your issue sounds like mine.

I have a revision D and a forge DV when I swapped between the two I no difference as far as the fluttering went.

[schmiesus]

Log the wastegate duty cycle. Put it in graph mode and drive around. When you hear the sound, look and see if it corresponds to a change in duty cycle.

And yes, the wastgate flapping open will definitely make chirping noises.

I'll do this on my way home today.

[schmiesus]

1st and 2nd unfortunately it was 92F up here yesterday

http://www.dubberz.com/uploads/boost2.png

[schmiesus]

3rd gear rolling pull at 40km/h @ 90F


http://dubberz.com/uploads/boost3.png

[schmiesus]

This shouldn't have oil on it like this should it :/

www.strikedesign.ca/downloads/IMG_0567.JPG

6psi it's opening up :/

[schmiesus]

Dumb question but should I be able to feel a ton of air coming out of the wastegate actuator and be able to move the rod with no effort at all when 10psi is applied?

[jimrobbington]

AFAIK, there should be absolutely no air coming out of the actuator. It is a sealed system. Check all three boost lines in that area coming from the N75 for cracks and leaks. You could spray really soapy water on it and pressurize it with a bike pump or something and look for bubbles.

[schmiesus]

It's coming out along the push rod

Like a lot. So I think I've solved my issue..... Well kinda

[schmiesus]

I am using an electric pump and it can't get above 10.2 psi and it's allllll coming out

[jimrobbington]

Hmm. That would lead me to believe that the actuator itself is cracked or something. I don't think that it is possible to buy the wastegate actuator by itself? Hopefully I am wrong. You can steal one from a used K03, or Forge makes an aftermarket one that I believe is intended for a transverse 2.0, but should be able to make it work. It's over $200 though iirc.

[schmiesus]

CTS Turbo is local to me I'll give them a call in the morning. As it is I'm putting her back together and in for the night