SR20DET low boost issue

[mdgeist]

I was driving to work this morning on the highway and noticed that my car wouldn't spool past 2-4 psi no matter how I step on the gas pedal.
I have a T28 w/ a stock wastegate on my redtop SR20. The waste gate vacuum line is connected to my intake manifold and the lines are still good.
I never push my car hard since it is my daily driver to work and home. I usually shift between 3000-3500 rpms.
I noticed the problem when I was going up hill and my car could not spool. I can hear the turbo spool at low rpms and the BOV still goes off.
Is the wastegate stuck? Or do I need a new one? And how would I fix the problem?

[Sugar]

Does it buck or hesitate in anyway, or does it feel fine and just not spool? I'm assuming its the second one since you mentioned no other symptoms. Most likely it is the wastegate. You should be able to take the wastegate off without to much hassle. Take a valve stem, cut it in half (so the fat end isn't present), slip a hose and hose clamp over it, then attach the other end of the hose to the wastegate. Apply pressure via air-compressor, it shouldn't move until 7 or 8 psi. Or don't even take the wastegate off, just get a really long hose .

Or just replace it while its off, my suggestion is if you are bored.

[mdgeist]

The car doesn't buck, but it will hesitate when you try to gas it. It will still sit at a traffic light and idle find. As long as I just cruise, the car drives pretty good. It does spool, but only at low rpms.
I'll try that valve stem idea this Friday or weekend. Will I still be able to drive my car to work?

[Sugar]

Check for boost leaks as well. Get a PVC Pipe Cap, and put it in your hot pipe right after the turbo or on the turbo inlet, put a valve stem in it, fill it with 10-20psi and listen for leaks.

The turbo doesn't build boost, can you still hear it spooling though? A bad wastegate shouldn't cause the car to hesitate at all.

[mdgeist]

After I thought about it. I think I could of damaged the wastegate too.
I was trying to tighten down and close the gap between the exhaust manifold and turbo due to a boost leak. The steering column shaft was in the way of the down pipe (I have a one piece 3 in. down pipe), so I zipped tied it to the wastegate to hold it in position away from where was I actively working in. Maybe that could also factored into what's happening?

[Sugar]

I doubt it, but if the problem didn't exist until after that it is likely.

[mdgeist]

This how it looks like as of now.





Where should I tap and weld a nipple to? To the turbo or the hotpipe?

[Sugar]

Tap and weld a nipple for what?

[GoTRicEo0]

Check the bypass valve and or take a vacuum tool and apply it to the waste gate. Drive around and check if it still allows boost.

[mdgeist]

Here's a update...
I took down the stock wastegate and applied sugar's theory by putting air through it with the valve stem. In the end, the wastegate did not move.
The bypass valve checked out good, but did not have a vacuum tool available.

So I went ahead and purchased a new wastegate... http://www.frsport.com/HKS-1430-RN005-W ... p_850.html
It doesn't bolt on since the bracket is off, so I will have to modify the bracket. And I'll report what happens afterward.

[mdgeist]

I installed the new wastegate and took the car for a test drive.
While driving... The turbo doesn't spool and BOV doesn't sound off.
When installing wastegate, should it be open or closed?

[Sugar]

The wastegate should be closed, it should take a decent bit of effort to open it by hand. If its open adjust the actuator so its closed tight.


You say you applied pressure to the wastegate and it did not move? This scenario would cause your turbo to never stop spooling...

Unless its just stuck in a somewhat open state.

[ciscos13]

just double check your clamps and make sure there is no leak from your cold pipe to hot pipe.