Wastegate stuck open.

[Skillz]

Ok, I have a Evo III 16G turbo, got it brand new from Mach V Motorsports. I also have the O2 dump.

Now, I just got all this stuff hooked up, and when I crank the car it runs, fine. No ruff idle, however, it sounds like it has a HUGE exhaust leak. So I looked under the hood, and the exhaust is coming out of the O2 dump pipe. It's like the wastegate is never closing.

I'm kind of new to turbos and stuff, but I thought this is how the wategate worked:

Vacum/low boost kept the wastegate flapper closed, but when boost (+ pressure) pushes against the wastegate acuator, it will push the wastegate open. Then, the air coming from the exhaust would escape past the exhaust turbine and thus, keeping the boost "controlled". If you placed a boost controller in front of that, set it to say 16 PSI, then it would take 16 PSI to open the boost controller, which would activate the "stock" wastegate, which is what like 8 or 9 PSI?

So, if that wastegate is stuck open, then boost will never be able to build up, which is what this seems to be doing.

Question is, how do I fix that problem, and what can cause it?

I do know, when I got the turbo I noticed the wastegate flapper was open. I didn't think it should have been like that, but being that I never seen a 16G turbo, I didn't know. Both my 14b turbos was sealed shut.

Thanks in advance for any help.

 

[xcelr8n]

can you boost when you drive? is it noticeably slower? is it just not making any boost at all.

 

[Skillz]

Nope. When I drive, boost gauge reads 0. I have vacum though when the car is idleing.

 

[PaleDSM]

Make sure the flapper door can swing freely from fully open to fully closed. Sometime the door will hit the O2 flange and get hung up.

 

[Skillz]

I think I figured out the problem guys.

Seems I may have the wrong wastegate acc. on the turbo. I took the arm off the flapper, and I could move it freely. While the car was running I moved the flapper all the way down till it was closed. I knew it was closed, because that ungodly noise went away. I compared it with the hole in the acc. and it was off by about 1/4 of an inch. So I turned the car off, and compared again, same results.

I am going to put some washers in between the wastegate accu. and the turbo housing to move that arm back, so that it will be closed.

I'll post the results when I get that done.

Thanks again everyone.

 

[Skillz]

Ok, got the washers on now, and it's working perfect. Well, almost.

My boost will go up to like 20ish+, and I'm not sure why. I turned the boost controller all the way out, and all the way in and it still does it.

What else could cause the boost to go that high?

 

[TurboJunky]

the wastegate sticking closed.

 

[Skillz]

Is it possible to have a bad wastegate? I mean, it's brand new.

 

[Skillz]

Better yet, what could cause it to stick closed?