Flutter under acceleration w/ 30FF

dk500 · 03-04-2018, 09:56 PM

So I don't think that this is a vacuum leak, and I don't have any logs of this but here is my issue -

-30FF code
-Under moderate acceleration, especially after shifting (auto trans), it sounds like there is a flutter, almost like my BOV will let off boost for 1/4 of a second, stop, then do it again. This sound doesn't occur at WOT.
-Only able to make about 6lbs of boost at WOT. Boost spikes to 9lbs when shifting, but then gradually falls back down to 6lbs

Car has JB4, and this issue seems like it doesn't matter what map I am on. Car is just as fast (or slow in this case) whether I am on map 5, 4, 1, or 0. I have checked all the vacuum lines and they seem fine. When I pull the lines off the vacuum canisters there is a significant woosh. The wastegates have some play but it is not much. It doesn't appear like they are binding when operated by hand, so as of now they do not appear to be the issue.

Where should I start for diagnosing this issue?

Mods list -
JB4
ECS Tuning charge pipe
ECS Tuning BOV with original spring that came with it
DCIs (issue persists when running w no filter for a test run)
Muffler delete
Alpina TCU flash

dk500 · 03-04-2018, 11:55 PM

Update - got some logs.

I have absolutely no idea how to analyze these other that it seems like my WGDC is going wild. The first pull was map 5 and includes shifts to show what I was talking about under part throttle, second wone is a WOT 3rd gear pull in map 4.

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NoQuarter · 03-05-2018, 12:44 AM

Whst size vacuum line you have to the BOV?

dk500 · 03-05-2018, 12:57 AM

Quote:

Originally Posted by NoQuarter

Whst size vacuum line you have to the BOV?

Whatever came with the kit which looks like it is a 3mm. I have it routed from the intake manifold nipple that operates the DVs

dk500 · 03-05-2018, 01:04 AM

Another log. 1st-3rd map 5. Updated JB4 to the latest firmware then took this.

Name: pull 3 mp5.jpg
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RSL · 03-05-2018, 04:49 AM

Upload CSVs to datazap if you want anyone to look at logs.

You're running 8psi peak (i.e. stock boost) with a target of 16psi. If you bought the JB4 used and didn't start with default settings, start there. Willing to bet dash menu 4 is set wrong though, like 4/4.

retrorafin · 07-21-2022, 05:30 PM

Did you ever find the problem? Have I b very similar issues, replaced all vac lines and adjusted wg arms, still sounds like it happens by my BOV thinking that's what it is

03-04-2018, 09:56 PM	#1
dk500 New Member 0 Rep 12 Posts Drives: 2008 E90 335i Join Date: Jan 2018 Location: Tempe, AZ iTrader: (0)	Flutter under acceleration w/ 30FF So I don't think that this is a vacuum leak, and I don't have any logs of this but here is my issue - -30FF code -Under moderate acceleration, especially after shifting (auto trans), it sounds like there is a flutter, almost like my BOV will let off boost for 1/4 of a second, stop, then do it again. This sound doesn't occur at WOT. -Only able to make about 6lbs of boost at WOT. Boost spikes to 9lbs when shifting, but then gradually falls back down to 6lbs Car has JB4, and this issue seems like it doesn't matter what map I am on. Car is just as fast (or slow in this case) whether I am on map 5, 4, 1, or 0. I have checked all the vacuum lines and they seem fine. When I pull the lines off the vacuum canisters there is a significant woosh. The wastegates have some play but it is not much. It doesn't appear like they are binding when operated by hand, so as of now they do not appear to be the issue. Where should I start for diagnosing this issue? Mods list - JB4 ECS Tuning charge pipe ECS Tuning BOV with original spring that came with it DCIs (issue persists when running w no filter for a test run) Muffler delete Alpina TCU flash
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03-05-2018, 12:44 AM	#3
NoQuarter Captain 168 Rep 906 Posts Drives: 2008 535xi / 2011 Z4 35Is Join Date: Jan 2011 Location: Indiana iTrader: (0) Garage List 2018 BMW X2 [0.00] 2008 535xi [0.00] 2011 Z4 35is [0.00]	Whst size vacuum line you have to the BOV?
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03-05-2018, 04:49 AM	#6
RSL Captain 650 Rep 779 Posts Drives: E92 ///M3 (Retired) / 335is Join Date: Mar 2012 Location: USA iTrader: (6)	Upload CSVs to datazap if you want anyone to look at logs. You're running 8psi peak (i.e. stock boost) with a target of 16psi. If you bought the JB4 used and didn't start with default settings, start there. Willing to bet dash menu 4 is set wrong though, like 4/4.
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07-21-2022, 05:30 PM	#7
retrorafin New Member 0 Rep 6 Posts Drives: 2007 BMW 335I Join Date: Jun 2022 Location: wi iTrader: (0)	Did you ever find the problem? Have I b very similar issues, replaced all vac lines and adjusted wg arms, still sounds like it happens by my BOV thinking that's what it is
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