2G Turbo won't build boost

[XalD]

I'm gonna start by saying I've been reading forum posts on various websites for days and haven't been able to find the problem.

I have a Hahn Racing 20G turbo and it won't build past maybe 7 psi, and my Greddy boost controller won't effect anything, and there's a ticking noise that sounds like a flutter but my BOV isn't moving until it's supposed to... I'm not sure where to go from here...

Thanks for any help

 

[dragon181]

maybe blowing wastegate open, if it is internal tie it shut, external increase spring pressure and test it but watch the boast guage because you do not want to much this is just to rule out wastgate.

 

[XalD]

Can you point me in the direction of how to properly do that? I don't want to just cause more problems for myself.

 

[Colin Roper]

I would also think the wastgate spring would be and issue. Maybe just check your tubing you might have a leak somewhere.

 

[XalD]

Brief update, a 30A fuse that I think may be the wastegate controller blows instantly when the car turns on... I'll follow the cord when it's lighter out.[DOUBLEPOST=1408936111][/DOUBLEPOST]What would be the easiest way to check for leaks?

 

[turtlebain]

Actually, fix electrical, then report back. What fuse is it?

 

[XalD]

I'm not sure to be honest, it's unlabeled in an aftermarket fuse box (I'm not sure what else to call it) but it is a 30A that blows instantly, and the boost controller powers on but doesn't seem to control anything at all so I'm thinking it may be a part of it.

I'm thinking I may try to disconnect the thing and see if the fuse blows or not.

 

[dragon181]

Find out why the fuse is blowing, what model and # is the boast controler

 

[XalD]

It's the Greddy Profec B-Spec II.

 

[turtlebain]

Sounds like he has a GReddy electronic boost controller. Probably the Profec B Spec II (a very common one).


Beyond your electrical problem OP, was it acting normal, then did you do XX, and it started acting this way? You could try running just wastegate pressure to see if your noise goes away, but I would really fix that electrical issue 1st thing.[DOUBLEPOST=1408938207][/DOUBLEPOST] I didn't see that he stated the model ^^

 

[XalD]

It happened after I put in a new stereo, I think it happened during the time of taking off and putting on the battery a few times while running wires.

How would I switch to just wastegate pressure?

I don't mean to ask such presumably obvious questions but I just don't want to cause more issues.

 

[turtlebain]

If you bypass the boost controller that's wastegate pressure which I think is 14 PSI (I most def. could be wrong about that).

It's possible you knocked a boost controller wire loose while installing the stereo.

 

[XalD]

I'll check all the wiring when it's light tomorrow, would that explain the instantly blowing fuse? I guess if it's a positive and it's sitting on a ground point but when I checked it looked like everything to the back of the controller was in and it turns on and all the functions and displays work just it doesn't effect boost pressure.

 

[turtlebain]

I'll check all the wiring when it's light tomorrow, would that explain the instantly blowing fuse? I guess if it's a positive and it's sitting on a ground point but when I checked it looked like everything to the back of the controller was in and it turns on and all the functions and displays work just it doesn't effect boost pressure.

It could, yeah. Loose wires creating a short, or bare wire touching another.

 

[XalD]

Then yeah I'll definitely check in the morning and report back.

 

[lasershark]

To bypass the boost controller and run straight wastegate pressure is simple. Grab some vacuum line and hook the wastegate actuator nipple up to the J-pipe nipple.

 

[Dsmkauai]

O.p. sounds like you either wired something wrong or have a loose wire shorting that fuse out. Go over your work! I really hope you soldered all your wires and not just twisted together with electrical tape or butt connectors!!

 

[pj91gsx]

The hahn t3 housings have a really bad problem with the valve getting more slack. When the slack becomes too great it causes the valve to stick open sometimes when closing.

This would cause your car to have a hard time building boost. Spool up time would be horrible also.

 

[JusMX141]

Baseline boost pressure (actuator spring pressure) should be roughly 7psi on a Hahn 20G....so it sounds to me like you just have no boost control whatsoever above stock spring pressure.

 

[XalD]

If it had just a hard time building boost because of too much slack wouldn't I still have some control over boost pressure?

Yeah it's more realistically about 6.8psi, that's why I'm almost certain it's an electronics issue.

 

[XalD]

So the fuse was too my turbo timer, which I believe is completely dead, but it still doesn't explain my issue.