Need help with BOV willing to pay

@Alkoran

Sorry, I originally bought the gfb but did not end up installing that I installed the whoosh BOV adaptor/spacer. I need to change my signature. But yes it’s the whoosh,

In that case you should not have any flutter at all like I explained, only "pshh" and "whooshing" sounds depending on if you're in boost or not and the lenght of time you keep the throttle closed. It's only a spacer and it can only be bolted one way so there's nothing that can go wrong on that part. If it was leaking because of bad machining or incorrect tolerances, you'd hear the leak constanly under boost, it would not affect the behavior of the BPV.

The BPV is either fully opened or fully closed, no in between and it will open every time the throttle is shut off, no matter if you're WOT/full boost or low rpm/under vacuum/cruising. Check that the electrical connector is fully seated on the solenoid.

Can you take a clip of the sound? I'm really curious to hear it.

You could also ask your tuner if he did something on the tune that could affect the behavior of the solenoid. I don't know if they do that kind of thing.

Stkid93 you should install the GFB DV+ /VTA it is a better unit that uses the stock connection but upgrades the spring and plunger from the stock recirculating valve. The spacer is just that a spacer to allow more air for whooshing sounds.

It's your bypass valve operating.

It's based on a number of parameters the ECU is receiving feedback for. Pressure, temperature, throttle position, load, spark, speed, etc. The ECU is looking for the best drivability and this includes when/how to vent the intake charge to make the car more responsive. We do not have traditional mechanical bypass valves with a simple spring. It's a solenoid that the ECU controls, and adjust as necessary quite quickly.


Under specific load and unload, the OEM bypass valve will flutter a bit. I was able to match the condition to get it to flutter even when stock. The BPV is not either fully open or fully closed. It's an ECU controlled solenoid and it can oscillate based on demand feedback into the engine. That's the whole purpose of it being electronically controlled, there's much finer resolution the ECU will adjust for. At partial throttle and lower-pressures, the car will ride the line between needing to vent pressure and wanting to keep the bypass valve closed for response. It's adjust this every time you let off the throttle.

Old spring-type bypass valves (or BOVs) are purely pressure based, but even those can oscillate due to pressure spikes as the spring stretches, the force pressure is vented, and thus closed, causing the pressure to build, repeat, etc.
Real compressor surge is due to the over-pressurization of the intake system while under constant load. When this happens, the engine can't consume the air enough and the boost builds up in the intake, regardless of the throttle-plate being open. This starts to cause a rear-flowing pressure wave/bubble that then propagates back into the turbocharger compressor, which is spinning at some 80K rpms as it's connected to the turbine whizzing at the same speed. So the engine is making power and positive pressure (boost), meaning the turbocharger has a more than adequate amount of gases moving through the engine to create enough energy to spin the turbine wheel, thus spinning the compressor wheel. While also having higher pressure spinning against the compressor wheel. This is what destroys turbochargers, as you get unbalanced torques, vibrations, warping/bending due to the mismatched and oscillating pressures. You can literally torque/twist components spinning at 80K. Carnage ensues.

The noise the byapss valve makes means nothing. It's a pop-off valve, nothing more. The design of the port, spring pressure (If a fully mechanical system), can influence the sound, but it only has to vent pressure over a certain PSI. Without a bypass valve the intake charge will simply be consumed by the idle air circuit eventually, but it's certainly better to have the pressure vented/bleed off quicker.

Unrelated, but if you're interested look into the Prodrive Rocket from their glory Subaru WRC days in the mid 2000s. They even patented the entire design so it's in the public space. It's a giant middle-finger to bypass valves, and it's one of the most ingenuous ideas I've seen in Rally in decades.

@the duke

I dunno, I never got any flutter on mine. It was always fully venting no matter under what conditions I drove. I'd be curious to hook a good scan tool to check if the solenoid pid is available for diagnostic purpose.

@Alkoran @the duke

Alkoran imma dm you to send clip of sound it says the file is too big

- I want to install the gfb unit that is the reason I started this thread (more info below)

ok well from what I’m gathering I should be okay? So here is what happened with the gfb unit (why I didn’t install it and ended up going with the whoosh spacer)

i got the unit used from a forum member. The kit came with the blow off unit itself, 3 longer replacement screws, a replacement spring and a replacement plunger. The forum member bought it from whoosh and on whoosh’s website the replacement plunger looked black. The plunger I got with the used kit was gold. Other than this they looked very similar. After watching installation videos on how to put the unit together and install it I found that the replacement spring goes into the electric solenoid that operates the BOV, the replacement plunger goes on top of the replacement spring. And then the stock electric Solenoid and the gfb unit are supposed to “snap together” the replacement plunger has a little nipple on one end and it looked like it just snapped into the gfb unit, they became 1 part, and you then used the longer supplied screws to install the combined units.

this was easy enough but the problem was the gold plunger I got did not “snap in” to the gfb unit. So I started thinking the guy sent me the wrong part. I had already taken 2 days off work and had a scheduled date to go up to max Morin to have the work done which was a 5 hour drive for me, a night at a hotel, and 2 days off work. so I needed something I knew would work for sure. So I bought the whoosh spacer for now until I figured out the gfb unit.

so I ended up buying a new plunger from Germany, I was fully expecting it to be black like in the pictures, but it was the same exact gold plunger I was sent by the forum member. So I contacted Ron @whoosh and he told me the plunger was supposed to be gold. But did not offer any other help beyond that. I still have the gfb unit sitting in my house but no one has been able to tell me how it’s supposed to work. I’ve watched several installation videos and took it step by step and i kee getting stuck ar the part where the plunger is supposed to snap in” So Im still stuck with the gfb unit until someone can help me figure out how it works because I don’t want to spend the time and money bringing it to a shop if it won’t work. Even if I don’t go back to max, it’s still labor time and money at another shop.

that’s the reason I started this thread, I want to install the gfb unit and I need help from one of you guys so we can figure out how it works and I don’t waste money.

Part 2

this is my exact problem, while I really appreciate your help and responses. I have @Alkoran telling me it shouldn’t flutter and @the duke telling me it should. I have been getting mixed responses from dozens of people not just you guys.

all I know is without the spacer I never fluttered . Because of my intake I could here the blow off very clearly even with the stock bypass valve but never flutter. And I’ve watched probably a dozen YouTube videos of fiestas using a BOV adaptor and from what I could tell none of them fluttered either. (Full disclosure they had boomba units and I have a whoosh unit)

Just curious but what are your boost levels? What were they before the BOV spacer and what were they after the spacer? If they are the same I would not worry. If you have a drop in boost that would indicate there could be something off with the stock BPV as they do crack and maybe that could be causing a flutter. You could take off the from passenger wheel get a flashlight and take a look at it. I had the boomba BOV spacer and 99% of the time it would be a loud psshhhhhhhh other 1% would be a slight flutter.

@agangel

Running 25.5 ish now, before whoosh v3 and whoosh BOV spacer I was running 26-26.5.

i had a whoosh v3 intercooler done at the same time as the BOV spacer. Boost dropped about .75 psi but that is from the pressure drop from the bigger intercooler. Other than that. boost and afrs are fine. Whoosh is sending me a replacement spacer so I can put the new one On and send the old one back for inspection but I don’t have the tools to do the job. I may end up having the new one put on just to see. When the car is still warming up, it vents 99% of the time just like you. But then after some driving it sounds like it stops venting completely. The best way I can describe it to paint a picture is that it almost seems like it works perfectly at first but the valve that is supposed to vent the excess air just completely stops working after the car warms up. I’m lost