25PSI! Arg! Wastegate not kicking in. Lines wrong?

[andyrew]

I got my turbo kit finally running, and aside from it wanting to die all the time at idle, it seems to be fine.. Oh that and my wastegate isnt kicking in at all.. so im getting full boost instantly...


What can I do here?

How would I mount a boost controller if I needed to go that route?

Does this look like I put the vaccume lines in correctly?






Thanks!!
Andrew

[andyrew]

The line coming out of the turbo is plugged off, and Im sure that is wrong.. Does that go to the wastegate?

[ct1.8t4me]

It looks like your N75 is plumbed completely wrong.

It should have:
Line going in to the TIP - looks like that is all set as that is how the N75 attaches.
Line coming from the compressor to the N75
Line going out of the N75 to the wastegate actuator.

It looks like you are using one of the other vacuum lines (the yellow) that is completely unrelated to the operation of the N75 - but I don't remember what it's for (emissions or something).

Also the line that actuates the DV should be dedicated. It comes from the intake manifold and goes to the DV and nowhere else if I am not mistaken.

[andyrew]

Do you know if the line going into the wastegate from the N75 goes on the part thats in line with the TIP?

TIP-------------- T ------- Wastegate
-------------------|
Turbo line (positive pressure)

where the T is the N75

DV should be dedicated, the only other thing its hooked up to is the boost guage, so that should be peacy..

[ct1.8t4me]

Looking at this: http://pictureposter.audiworld.com/12010/audin75.jpg

It seems like the output to the wastegate is across from the nipple that inserts into the TIP and the input from the compressor is the one that comes in perpendicular.

So, yes, I think, to your question.

I will go look at my car when I go out to lunch if no one else answers definitively before then.

[andyrew]

Now thats a good picture! Im at work now, couldnt get to changing it before I drove the car (Wanted to get used to the clutch... and find any more potential issues).

When I get on a break, I'll swap it around, I brought some vaccume lines so I can do such..

[1NaudiA4]

I was using a manual boost controller on mine so thats why the line is plugged off. How'd it pull?

[andyrew]

Dont know, it boosted to 25psi at like 3k almost instantly so I got off of it, It felt weird too. (Although it did feel like it was about to take off REALLY hard)


I plugged the line.. not you :)

[andyrew]

Brought the wrong sized vaccume line... arg

[andyrew]

Actually I should mention that my boost guage goes to 25psi, so I was scared that I could be way overboosting..

[creechsa4]

watch your bends in your wastegate lines, it may kink under heat. i use 1/4 inch carb fuel line and try to keep the curves gradual.

[andyrew]

Thanks! I dont think I have an issue with bends, they are pretty smooth.

Got it going, Im able to drive full throttle but the boost comes on really late... Then it just rolls on.
Keeps getting more boost till 7k.. powerband is 4.5-7k, 15psi at 5k.

A/F ratio is rich, 10.5ish.

Keep in mind im on a 93 program with 91 octane, however I am running a FMIC. where its not required.

Im thinking my N75 valve could be backwards ie TIP switched with wastegate..


I have one more line to run and thats the odd vaccume line after the MAF, Its currently open so I should be running a little lean (which I am at idle, 15-16). I need to connect that line to the black tube, but its too hot to get in there now..

Anyways, It drives good enough now that i'll take it like it is even if I cant get the boost to come on earlier.

[AudiRacerS4]

you should be using an MBC or EBC not an N75 with that turbo.

[andyrew]

you should be using an MBC or EBC not an N75 with that turbo.

Dad posting on Andyrews account

I have one of the black MBCs. Can you tell us how it would connect?
One end to the port on the compressor side of the turbo, one end to the wastegate?

I think there's a third port, but we didn't use it on my car.

Thanks.

[AudiRacerS4]

Dad posting on Andyrews account

I have one of the black MBCs. Can you tell us how it would connect?
One end to the port on the compressor side of the turbo, one end to the wastegate?

I think there's a third port, but we didn't use it on my car.

Thanks.

yup one end goes to the compressor housing and the other end to the wastegate

[andyrew]

Whats a good PSI to put this thing to? 18?


Thanks all!
Andrew

[1NaudiA4]

I had mine set to 20 but 18 would be fine... could really be set anywhere from 18 to 23 though

[1NaudiA4]

Did you get all the quirks worked out with the kit? does it pull nicely?

[andyrew]

It seems to pull nicely, I think I have it set at 20psi, but I couldnt really monitor it. I was getting some stumbling/detonation at lower RPM's when trying to pass someone and that was me at about 93 octane...

I have 5 gallons of 100 in my trunk for when I hit the track, I'll put that in and hopefully I wont get any detonation.

It has a strong continuous pull, but I'll say this. I Am getting an electronic boost controller, It just has to have one to get the low end TQ that I want for autox.

It sounds fing amazing too...