2G T25 won't hit "full boost"

[smills1840]

So after filling up with Shell premium the other day (I doubt that's relevant), I noticed that no matter what I try, I can't get my stock t25 to hit "full boost". I put quotes around full boost because I don't have a boost gauge yet, so I'm still using the stock one. Trust me, I know it shouldn't even be considered a boost gauge, but I haven't bought a real one yet.

Anyway, I can rev this bi*** out to 7000 RPMs in any gear and it still won't reach the top of the boost gauge. I can also definitely feel that it isn't pulling as strong as it used to.

This is a completely stock 2g dsm, with the exceptions of the dump tube mod and a 3" cat back.

I've done a BLT, with no leaks.

I've checked my wastegate, and it moves freely. Even if the wastegate actuator is stuck, it's stuck in the closed position so it should let me build full boost and beyond.

From what I can tell, there aren't any exhaust leaks pre-turbo. There is one post turbo, but it's not bad and it's always been like that (long before this problem started)

I've checked all vacuum lines and the MAF connector, all good to go.

I've run it with and without the BCS, still no good.

The only thing I haven't done is pull my exhaust/downpipe off and see if it's clogged.


I cannot think of anything else that would be causing this. Do you guys have any ideas?

 

[AngelOfPassion]

I really hope 87 was not put into the tank!

Would be funny if that is all this was . Has the OP even come back to say anything? haha

 

[undefined0000]

He did say shell premium, unless he derped and hit 87 by accident

 

[kleenf4i]

another " unsolved mystery"

 

[Robzone0911]

Are you running a boost controller, boost T, or manifold pressure to the wastegate actuator?

 

[smills1840]

No 87 has ever been near this car. Only 93 premium, and that's what's in there now.

I need to make another BLT, because the one I have now is hard to read. I'm pretty confident that I don't have any leaks, but I'll test again tomorrow.

 

[Alan11]

Dirty MAF ?!?!?

 

[VivaLaOC]

There is no way to know if your t25 is hitting 12-14psi with the stock gauge. Unless you get a real boost gauge you will never know. The stock gauge is just controlled by the ecu, not actual pressure. I don't think it ever reaches the top of the gauge anyways.

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It absolutely does reach the top o