[N54Fiend]

Anyone here running dual port DVs?

I purchased a set used from a member here and just installed them on the car. I’m having two weird issues:

1) On cold start I hear what sounds like the DVs opening and closing one after another until the car finishes the cold start cycle.

2) When building boost then releasing throttle I hear one valve open, then the other open quite a while later. Under some circumstances they go back and fourth and I hear 4 or even more bov sounds in succession.

I haven’t adjusted them after opening the box, that’s obviously what I need to do first and see where I stand after that. Wondering if anyone has had something similar happen, and if so, did an adjustment fix it?

Any adjustment pointers would also be appreciated. Are you running yours max soft or did you adjust to a “harder” setting. Also, did it take fine tuning to get them to release the pressure at the same time/pace?

Thanks!

[_N54]

I had those DV's. You just gotta play with the adjustment since it came off another car which is why I decided to get a Tial bov after upgrading my turbos.

[mweisdorfer]

I use the Forge DV's with the yellow springs..

[Bimmer_Bro]

Originally Posted by mweisdorfer

I use the Forge DV's with the yellow springs..

Me too. I vent mine to atmosphere for extra whoosh lol

As mentioned above you just need to keep adjusting the Turbo smart ones. They are bullet proof once set up tho.

[BSM n54iS]

I had them before and had them and like half open, so around 3k and above it would vta. I think you should adjust both to full tight, make a clocking mark on each, and count the turns to adjust them both to the same setting.

[N54Fiend]

Thanks everyone for the info. I took apart both DVs this weekend to ensure there wasn't any obvious issue with the parts. Neither have shims installed, and both have pink springs inside.

Below is a video demonstrating the sounds on cold start. Haven't yet diagnosed this issue... I think my first two tests will be to cold start with the vacuum connections to the DVs unplugged and capped. And also to unplug the electrical connections to the boost solenoids during cold start to see if it's a waste gate issue or a DV issue. Any other suggestions?

[Bimmer_Bro]

Originally Posted by N54Fiend

Thanks everyone for the info. I took apart both DVs this weekend to ensure there wasn't any obvious issue with the parts. Neither have shims installed, and both have pink springs inside.

Below is a video demonstrating the sounds on cold start. Haven't yet diagnosed this issue... I think my first two tests will be to cold start with the vacuum connections to the DVs unplugged and capped. And also to unplug the electrical connections to the boost solenoids during cold start to see if it's a waste gate issue or a DV issue. Any other suggestions?

You need to try what has been suggested. Tighten them both fully and then experiment but making them softer together.
Do not unplug your boost solenoids, there is no point. This is 100% your DVs making this sound not your waste gates. Also so not take the vacuum lines off the DV. They will just stay shut and not operate at all.

[N54Fiend]

Originally Posted by Bimmer_Bro

You need to try what has been suggested. Tighten them both fully and then experiment but making them softer together.
Do not unplug your boost solenoids, there is no point. This is 100% your DVs making this sound not your waste gates. Also so not take the vacuum lines off the DV. They will just stay shut and not operate at all.

Thanks, I'll give this a try first then. It's opposite to the suggestions given by TurboSmart... They suggest starting full soft and working your way harder.

[Bimmer_Bro]

Originally Posted by N54Fiend

Thanks, I'll give this a try first then. It's opposite to the suggestions given by TurboSmart... They suggest starting full soft and working your way harder.

Either way will work. It's just going to take some trial and error to get them dialled in correctly and opening together.
If this turns out to be a pain, you could switch for the Forge Dv which are directly plug and play with no adjustments. (Other than the extra springs included)

[N54Fiend]

Originally Posted by Bimmer_Bro

Either way will work. It's just going to take some trial and error to get them dialled in correctly and opening together.
If this turns out to be a pain, you could switch for the Forge Dv which are directly plug and play with no adjustments. (Other than the extra springs included)

I believe today I determined this is not an issue with the DVs.

I cold started it with the DVs on both full soft and full hard settings. Both ways it produced the weird sound on cold start. I then cold started it with the boost solenoids unplugged; No sound.

I’m going to dig a little deeper, but I believe it’s either an issue with the boost control system (solenoids, vac system, etc), the install, or the wastegate itself.

Any suggestions from here?

Thanks!

[N54Fiend]

Bump - looking for any feedback or ideas…

I read that some people are upgrading their BOV vac lines to 1/4” ID hose. Could I need to do this for the TurboSmart Dual Port DVs?

[Bimmer_Bro]

Originally Posted by N54Fiend

Bump - looking for any feedback or ideas…

I read that some people are upgrading their BOV vac lines to 1/4” ID hose. Could I need to do this for the TurboSmart Dual Port DVs?

The tial bov needs 1/4 line to operate properly. I believe yours will run fine on the stock 3.5 line. However I upgraded my DV lines to a 4mm and it did make them slightly more responsive. There is also just online to use a different vacuums source other than the intake manifold nipple. I doubt any of this is causing your issue.

How would you describe the sound on start up? Is it the back and forth air sound from the video? Or does it sound metallic?
How old are your boost solenoids?

[N54Fiend]

Originally Posted by Bimmer_Bro

The tial bov needs 1/4 line to operate properly. I believe yours will run fine on the stock 3.5 line. However I upgraded my DV lines to a 4mm and it did make them slightly more responsive. There is also just online to use a different vacuums source other than the intake manifold nipple. I doubt any of this is causing your issue.

How would you describe the sound on start up? Is it the back and forth air sound from the video? Or does it sound metallic?
How old are your boost solenoids?

It’s the back and fourth sound in the video. The pistons in the DV are not moving while this happens, they remain completely closed. The noises are coming out of the intakes. Seems to be alternating from one intake filter to the other, back and fourth.

I replaced the boost solenoids and all vacuum line with the new turbos, so they’re brand new.

[Bimmer_Bro]

Originally Posted by N54Fiend

It’s the back and fourth sound in the video. The pistons in the DV are not moving while this happens, they remain completely closed. The noises are coming out of the intakes. Seems to be alternating from one intake filter to the other, back and fourth.

I replaced the boost solenoids and all vacuum line with the new turbos, so they’re brand new.

Very strange I have never heard of this happening. This is only on start up? Does the car drive normal?
Your waste gates must be opening and closing which to me says vacuum issue or solenoid issue.
I assume the solenoids are oem brand?
I would confirm both canisters are not leaking and double check your lines route like this:

[N54Fiend]

Originally Posted by Bimmer_Bro

Very strange I have never heard of this happening. This is only on start up? Does the car drive normal?
Your waste gates must be opening and closing which to me says vacuum issue or solenoid issue.
I assume the solenoids are oem brand?
I would confirm both canisters are not leaking and double check your lines route like this:

The car seems to drive ok. I haven’t pushed it hard as I’m still on Ken’s base map and haven’t sent over a log for him to look at yet. It definitely has a bit of this same surge after building boost and letting off the accelerator though. I hear the DV’s open but then I hear the surge shortly after, same back and fourth sound.

I’ll check the routing next time I get to the car, later this week or over the weekend. I’m 99% sure I got it right as I had labeled everything well, but no harm in double checking.

The solenoids are Pierburg (PIE-700887190). My old OEM ones were working fine, I can always swap them back in for testing.

I’ve put 25 miles on the car since the swap - just needed to bring it to my Indy mechanic to reset something in the FRM which he couldn’t do anyway, I ended up doing it myself with ProTool.

The car was fine for those 25 miles. A few days later the car started leaking from the oil feed line connection at the block. Unfortunately it looks like I’ll be taking off the subframe again this weekend. I really thought I was in the clear. Finished the swap over a month ago and no leaks. This one popped up out of nowhere and started leaking like a faucet.

Edit: forgot to mention, I took a close look at the waste gate actuators on cold start, I dont believe they were moving either. I also dont believe I have a leaking vacuum canister because when I unplug the vacuum line from the canister after shutting the car off, there is still a vacuum there which I can hear hiss away once I disconnect the line.