[mastamike911]

EDIT 03/29/16: SOLUTION FOUND! See post #53


Hey everyone,

Recently I decided to get these items installed on my car (2011 BMW 335is):

• Pure Stage 2 N54 turbos
• VRSF 2" inlets
• BMS OCC
• NGK spark plugs gapped at .22
• New Bosch coils
• RB PCV Valve
• New stock Behr radiator
• Walnut media blasting
• Fresh oil change/coolant flush
• MHD Custom Wedge flash

Aftermarket parts that were previously installed:

• ER charge pipe
• HKS SSQV 4 BOV
• ER 6" competition FMIC
• VRSF kittyless DPs

After getting my car back from the installer, I am having an issue I was hoping y'all might be able to help me track down. I am getting weird noises in the engine bay during steady driving at low/zero boost levels (accelerator partially down, slow or no acceleration). For lack of a better description, it sounds to my naive ears like the BOV is pushing and pulling air rapidly. I'm pretty lost as to what the issue could be, so I stuck a GoPro in my engine bay and took a video, as well as took some data logs.

Here's the video (the weird sounds start around 3:56 if you want to skip to that):

Here is a data log I took while the sounds were happening:
http://datazap.me/u/mastamike911/log-1454894488

The car seems to run fine during pulls at WOT, and I took a few logs of those pulls if you would like to check those out to:
http://datazap.me/u/mastamike911/log-1454803990
http://datazap.me/u/mastamike911/log-1454804082
http://datazap.me/u/mastamike911/log-1454804146

Anyway, let me know if y'all have any idea what might be going on. I'll be taking my car back to the installer this weekend to have a look at it and I'm trying to gather as much info as I can before then.

Thanks!

[Lambobimmer]

It is difficult to hear on your video but I can probably tell you what is wrong. I had a similar issue and it started after I installed Pure S2 turbos and Inlets. Basically, you have thrown the balance off on your BOV and it is causing fluttering issues. I am not that familiar with the HKS but I had to change to a smaller spring on my Turbosmart BOV and it got much better.

[Jeff@TopGearSolutions]

First thing that came to mind was boost solenoids but im not 100% sure. If wedge says its not tune related then the BOV would be the next step if not boost solenoids.

Wish I could help more but this is a very new problem to me.

First step is to measure vacuum at idle to ensure the BOV spring is correct.

[Brule]

Exactly the same sound as socket in Australia section.
He tried 6mm vacum lines, softer spring in tial bov and still has it.

[mastamike911]

Originally Posted by Brule

Exactly the same sound as socket in Australia section.
He tried 6mm vacum lines, softer spring in tial bov and still has it.

Can you cross-link that forum thread?

Edit: NVM I think I found it http://www.e90post.com/forums/showthread.php?t=1177332 . It would be great if harms could tell me if he's getting the same thing I am. I don't believe I experienced any RPM surges though... After this big install, I did not do any adaptation resets at all. I wonder if that would be a good idea to do or not?

[mastamike911]

Decided to take an cold start idle log with one rev at the end tonight. You can find it here: http://datazap.me/u/mastamike911/log...ark=42-497-535

Does everything look normal? Could someone tell me what this means my idle vacuum is?

[Kienvu14]

Sounds like a train!!!

[FastHackem]

Honestly, to get an accurate reading you're going to need a mechanical gauge hooked directly to a vacuum line. The logged data is reading from the MAP sensor on the CP and not necessarily a great place to measure vacuum. That being said, most people report vacuum at idle to vary between -15-22PSI averaging around -18PSI. As the car warms up, the vacuum should increase slightly. Make sure your AC is off while testing as this load can skew the numbers.

[Sean978]

I'm getting something SIMILIAR but not quite as drastic... Only under partial throttle .... very weird oscillation.

After looking at your initial post you're also on different turbos, different inlets, different charge pipe, and different BOV than I am. (I'm running hexon RR600, PR inlets, VRSF CP and Tial BOV) ... do you have a jb4?

[mastamike911]

Originally Posted by Kienvu14

Sounds like a train!!!

Toot toot!

Pulls like a train, so I guess it should sound like one...

[Tiago@VRSF]

I'd get an accurate vacuum reading from a mechanical gauge as suggested. Your BOV may be set too hard or soft if it's not performing correctly.

[FastHackem]

Originally Posted by Tiago@VRSF

Your BOV may be set too hard or soft if it's not performing correctly.

Multiple people report that possibility, but the fact remains that the HKS SSQV4 is a non-adjustable dual valve pull type sequential BOV. According to the logs, it seems the BOV is operating as intended by releasing pressure when there is a difference between the main chamber, pressurized by the CP, and the rear chamber, pressurized by the vacuum line. Unless he has a knockoff, which I doubt he does considering the money invested elsewhere, I doubt the probability that the BOV is the problem.

What confounds me is, what is causing the extremely wacky wastegate cycles and boost pressure signals at cruising speeds and equal loads? I believe if this problem is solved, so will the Darth Vader breathing sounds heard in the video. To me, I either suspect an air leak somewhere, (most likely) or boost load tables requiring adjustment (possible). Hopefully, Wedge will provide some insight soon.

[BlackBB6]

Same noise for me, Pure S2, PR inlets, HKS BOV.

[bigdnno98]

Interesting. I'm in for results.

[mastamike911]

Originally Posted by BlackBB6

Same noise for me, Pure S2, PR inlets, HKS BOV.

Have you tried any troubleshooting?

[Lambobimmer]

I know what you are experiencing, because I went through the same thing. It is not the turbos but it is the inlets. The stock inlets are plastic and they do not expand and they also don't allow as much air to pass through them. The combination of more air and the fact that the silicone inlets can expand is throwing off your BOV balance. I had the same issue with my Pure turbos, VTT Inlets and Turbosmart BOV.

Prior to inlets it operated perfectly. I don't think that you will be able to fix the BOV fluctuation issue unless you can adjust your BOV. I tapped my intake manifold and switched my vacuum line to 6mm and I also went with a smaller spring and that got rid of almost all of my surge. There is another thread that also addresses this issue. Take a look at this thread:http://www.e90post.com/forums/showthread.php?t=1143824

[BlackBB6]

Originally Posted by mastamike911

Have you tried any troubleshooting?

I tried some adjustments with the JB4 wastegate position but they didn't make a difference.

I'm going to try a larger vacuum source for the HKS, if that doesn't do anything then I will get the HKS to Tial flange and go that route.

[Grand_hustle17]

Subscribed. Im sure after my hexon i will get the same with vsrf inlets

[DR-JEKL]

Socket vtl

[Socket]

Originally Posted by mastamike911

Hey everyone,

let me know if y'all have any idea what might be going on. I'll be taking my car back to the installer this weekend to have a look at it and I'm trying to gather as much info as I can before then.

Thanks!

I have exactly the same problem after installing RBs and VTT inlets... Am running a 50mm Tial... Ive increased the size of the vac ref line to the BOV, put in a softer spring but stil have the problem... A tune definately helped reduced the problem but it is still there..... very interested in what you find out

Link to my thread where you can hear the sounds im getting

http://www.e90post.com/forums/showth...080234&page=33

[mastamike911]

Originally Posted by Socket

I have exactly the same problem after installing RBs and VTT inlets... Am running a 50mm Tial... Ive increased the size of the vac ref line to the BOV, put in a softer spring but stil have the problem... A tune definately helped reduced the problem but it is still there..... very interested in what you find out

Link to my thread where you can hear the sounds im getting

http://www.e90post.com/forums/showth...080234&page=33

Hey Socket, thanks for the reply! It's good to know that I shouldn't waste my time buying a Tial in hopes to fix this. Hopefully WedgePerformance will reply to my email soon. He would be able to better look at the logs and see if there is something tunable.

[BlackBB6]

How detrimental to our turbos is this? I try to manipulate the throttle so it doesn't happen, but if it's going to cause damage I'm going to drive my Honda for a bit.