Can't control boost with any boost controllers.

[mk3-4-me]

So my wastegate doesn't seem to want to work with any controllers. I tried a manual and now my blitz EBC I hooked up. When it's hooked up, it will just go to 6 lbs no matter the settings of boost. I have a knock off external wastegate. I have everything hooked up correct, but it just won't hold any more.

I had the top vacuum port on the WG hooked up to the compressor to keep it closed to see if it will boost past 6, and it goes to 15 lbs easily.

Any suggestions? Just buy a good wastegate? I mean if it holds boost when I have just the top vacuum on, should it work when it's hooked up to a boost controller??

 

[Zumtizzle]

Exhaust Leaks?

Bad Wastegate?

 

[mk3-4-me]

No exhaust leak... At least not until the WG opens, then theres a big one! Haha jk

But ya like I said it holds great when only the top port is connected to keep the diaphragm closed. But when I have the bottom vacuum line hooked up straight to the turbo or a boost controller it just goes to 6ish psi. it's like any sort of air pressure going to the bottom vacuum port will cause it to open at 6 psi.

 

[stevenr816]

What boost does it run with nothing hooked up to the WG at all?

 

[barkz]

junk wastegate or BC hooked up wrong would be my bet. i was running 14psi on my stock WG and a MBC, no issues

 

[Dan_Gyoba]

Define "top" and "bottom" ports.

One port will push the gate open with boost, the other will push it closed. For mine, I just have a boost signal through a controller going to the one that pushes it open, and the other is vented to atmosphere. This works the same way the stock one works, so that when the controller lets boost through, it opens the wastegate.

Basically, my wastegate will open whenever there's 6-7 PSI more pressure in the one port than there is in the other, so the boost controller works to reduce or eliminate boost pressure in that port until the desired boost is reached.

If you have those ports reversed, then you'll get exactly the same effect that you'd get with no boost controller at all, provided that the boost controller is set to higher than stock. Set the boost controller to lower, and you might get no control at all, ie: both sides of the wastegate get the same pressure, and the wastegate NEVER opens. Overboost, here we go!

 

[mk3-4-me]

I don't really know what happens when there's no vacuum connected at all. I'll try that today.

But "top" as in the vacuum on top of the wastegate, and "bottom" as the bottom port on the wastegate. Lol

If it was a bad wastegate, would it hold any boost at all? Cause when the bottom vacuum port is hooked up, it will hold about 6 psi.

 

[mk3-4-me]

I'll check and make sure I have everythin hooked up but I'm sure I do.

And it's not a stock turbo.

 

[cyberdx16]

I'm having the same issues with my apexi avcr controller but have realized that I have my lines hooked up incorrectly.

The boost solenoid has 3 ports on it which I did not know. The previous owner of my car had this hooked up to the stock ct26 which only has one port on the wastegate. The two ports on my boost solenoid I would use are COM and NO. COM goes to the stock wastegate and NO goes to compressor housing nipple. Now that I have an external wastegate I have to switch my barb fitting on my boost solenoid from the NO to NC and route my vacuum lines accordingly.

So with my external wastegate my vacuum lines should follow as

Top port of wastegate to COM
Side port should be tee'ed to NC and to compressor housing nipple.

I hope this helps, I am glad you posted this because I overlooked my vacuum diagrams and have finally realized what I did wrong.

 

[mk3-4-me]

Lol well I have a blitz SBC EBC, do I don't know what the COM and NC is to be honest. I just have an IN and OUT on my solenoid. But I will double check my vacuum routing, but I'm sure I had it correct.

 

[barkz]

I'll check and make sure I have everythin hooked up but I'm sure I do.

And it's not a stock turbo.

kind of a given...

 

[mk3-4-me]

Well I was just stating it cause someone said how they had it on their CT. I guess it is a given. Lol

 

[mk3-4-me]

Ya with no vacuum hooked up at all to the WG it doesn't open.

So now what?

 

[hvyman]

Sounds like it's hooked up backwards. On NBC the ball should be on the compressor side.

 

[mk3-4-me]

its just a bleeder i believe. i can take the whole + - boost knob out and theres nothing in there. Maybe its just missing it? i got it free.

But anyways i have my EBC still hooked up and it still doesnt work... ?

ill double check everything now.


this is the MBC i have minus the T thing. Is this supposed to have a ball and spring?

 

[mk3-4-me]

ok so i kinda got somewhere. I tried the MBC like in this picture below



but that just opened at 6 psi no matter the setting. But then i tried it with the top WG vacuum line going to the "normal vacuum tee" and the bottom port going to the "regulator" and it held at 10 lbs. I opened the MBC up a little bit to see if that raises the boost a bit. But ill check that tomorrow when i go to work.

But ya isnt that wierd that i have to have it backwards?? And is there supposed to be a spring in the MBC i have? cause that would make sense then i guess.

Now idk why my Blitz SBC EBC isnt working. With that any boost setting just opens up at 6 lbs. I just tried it with the 2 different WG port switched and nothing for either of them. Maybe my Solenoid for it isnt working?? any of you have a Blitz SBC EBC?

 

[barkz]

dont be suprized when u hit FC

 

[mk3-4-me]

Y would I hit FC now?

 

[barkz]

if your messing around with BC and go too far, you'll hit FC

 

[mk3-4-me]

Well ya I know that... Lol I thought u meant at 10 psi now. I've gone to 15 with no probs.

But I just thinks it's weird that I needed to route the vacuum lines backwards for it to work for me.