APR K04 Boost Flutter Normal?

[CtNxFLeX]

Hey you guys.

So I found out my original DV finally got blown after running stage 1 and stage 2 for 3.5 years. It also lasted for 2 weeks running APR K04 surprisingly. I had it replaced with revision D and it runs back to normal except for the new fluttering symptom.

I've never had my boost gauge flutter before. This would happen when WOT starting around 2k between 3.5-5k rpm on any gear when hitting around 22 psi. It would go between 21-23 very rapidly and you could hear it in the engine so I know its not the gauge. After 5k, it would smooth out steady around 21psi.

The weird thing is when I'm starting at around 3.5k rpm and on WOT, hit hits 25 psi and then stays steady around 21psi without any fluttering.

Is this normal? I took some logs and wondering if anyone who has an APR k04 kit is experiencing the same thing or might know what is the problem from seeing the below logs?

https://www.dropbox.com/s/2qgq39lhpd...r-wot_run1.CSV
https://www.dropbox.com/s/mhxw2hi4ul...r-wot_run2.CSV
https://www.dropbox.com/s/b85nu7bed9...r-wot_run3.CSV
https://www.dropbox.com/s/0towh1bsko...r-wot_run4.CSV

[bacillus]

Lots of folk experience flutter with a mapped K04 and it's not a sign of something being amiss.

[CtNxFLeX]

okay, so I guess it's normal and nothing to worry about?

Does anyone who has an APR k04 FSI doesn't experience this issue and peaks boost around 25 and steady around 21?

I cant tell if this is normal or not because my previous DV Revision C didn't have this problem. Then again, it could of been on the way of deteriorating and dying on me which was why I didn't experience the flutter scenario which should have happened if I had a good working/strong DV in the first place.

Felix

[Rub-ISH]

no one has really ever fully assessed weather this is normal. I have a Ko4 and have tried just about everything to get it smoothed out...It still happens occasionally

I've gone as a far as putting a fluid damper, trying 3 intakes, and making wastegate adjustments...it still happens just not as frequently. GIAC has no idea about what it is, and APR never really wanted to address it because of the my intake choice

[ROH ECHT]

Usually this happens when your boost is on the edge of being too much, and you throttle boost it creating more boost than it will give when simply floored. I used to reach 26 psi when throttle boosting where it only gave me 23 psi when floored. It nearly always fluttered unless I floored it.

Now after having done another w/g adjustment, the boost reaches 21.5 psi peak and 18.5 to red-line. It still can be throttle boosted (increasing boost with a slower throttle) up to 24 to 25 psi, but the flutter is greatly reduced. It will however seem to flutter if I change the throttle position slightly while throttle boosting, but this is coming from the dv releasing boost due to the increased boost pressure.

I would say try getting the actual boost to meet or be slightly under specified boost by adjusting the w/g actuator, and keeping a WOT while logging the data.

[CtNxFLeX]

Hi Everyone,

Thanks for the posts. So I sent my logs to APR and they got back to me yesterday. Chris Teague from APR replied back sharing that it's normal and the logs look great and what they expected from a k04 FSI Kit.

I'm just a bit annoyed by the flutter noise, but if it's normal and nothing is wrong with my car, I can't complain.

Thanks everyone!

[mikey3117]

Hey guys! I had the APR K04 kit installed on my car about 3 weeks ago. About a week after install, I noticed this flutter. It is definitely an annoyance! I've read other threads where it's declared normal, others don't... I called APR and talked to someone who basically dodged the question!

Also after the install, my idle has been bouncing up and down and the car stalls usually at least once a day. Of course I need to get it to my shop for logs so we'll see...


BUT the car is fast!

[CtNxFLeX]

Hey Mikey! Congrats on the K04. Ever since I got it, it's hard to be light footed. I use to save gas to get the most MPG for my car, but ever since I got the K04, it's just too hard =) Save up extra money for gas as well =D

Regarding the idle issue, i had a similar issue. Turned out one of the boost tap hose I used broke. I guess it couldn't handle the 25-27 peak PSI. Ever since then, I got a CEL and realized one of the hoses ripped in half causing the erratic idle. Make sure your shop checks to see if there are any leaks, possible while installing something got loose or wasn't tightened well. Good luck and keep us posted. Can only hope it's that.

P.S: I'm not sure if you have stock or aftermarket intake, but I'm going to go back to the APR Intake or stock. My Evoms intake amplifies the fluttering noise. Hopefully doing so will not annoy me as much

[mikey3117]

Hey Mikey! Congrats on the K04. Ever since I got it, it's hard to be light footed. I use to save gas to get the most MPG for my car, but ever since I got the K04, it's just too hard =) Save up extra money for gas as well =D

Regarding the idle issue, i had a similar issue. Turned out one of the boost tap hose I used broke. I guess it couldn't handle the 25-27 peak PSI. Ever since then, I got a CEL and realized one of the hoses ripped in half causing the erratic idle. Make sure your shop checks to see if there are any leaks, possible while installing something got loose or wasn't tightened well. Good luck and keep us posted. Can only hope it's that.

P.S: I'm not sure if you have stock or aftermarket intake, but I'm going to go back to the APR Intake or stock. My Evoms intake amplifies the fluttering noise. Hopefully doing so will not annoy me as much

Yeah...lol Gas mileage has gone down!!! It's really hard not to push this car now. I have noticed though when I drive easy, it's really just a slight decrease. But I rarely drive easy..

I've had idling issues before related to boost leaks etc. Its always fun tracking these things down, but when you increase boost over stock, we have to expect issues.

I used to have the BSH True Seal intake but I didn't like the loud, whistling open element design. At the same time I did the K04 install, I had them put on the new VWR intake which is a ram style. Sounds amazing! It has quieted things down but has a nice aggressive growl when getting on it...

I do want to address this flutter though and will keep a close eye on the forums.

[NEW2B]

Hey guys! I had the APR K04 kit installed on my car about 3 weeks ago. About a week after install, I noticed this flutter. It is definitely an annoyance! I've read other threads where it's declared normal, others don't... I called APR and talked to someone who basically dodged the question!

Also after the install, my idle has been bouncing up and down and the car stalls usually at least once a day. Of course I need to get it to my shop for logs so we'll see...


BUT the car is fast!

when i first installed the k04 i had similar idle issues with the bouncing. ended up changing the spark plugs (ngk gap at .028 i think,) and replaced coils. this resolved all issuesffor 10k miles, up until a few days ago i noticed the fluttering has come back but no other issues , the gauge sometimes flutters but the car runs fine.