Car sounds like it's running rich until it warms up.

I never do any boost driving until I see the gauge starting to go up knowing that the car is still in rich mode until the system is in a 'closed loop' mode for normal operating temperature and operation.

It even mentions that in the car manuals that are equipped with turbo operations - no boosting until vehicle has warmed up.

How long has it been since the fuel filter was replaced?

Everytime my car starts to buck or act funny it is almost 100% of the time a boost leak. I have stock IC piping like you so that could be it, otherwise my problem is my battery terminal acts up and it runs off my alternator, and when it does the fuel pump acts up and the clutch is a bi*** to control from a start (almost kill it a hundred times, buck around in 1st gear...ugh) because of the inconsistent fuel flow. Have to jiggle my terminal to get it okay.
Anyways... most likely a boost leak from what i have experienced, and it always tends to happen in the cold for me as well so, just a suggestion to check for.
Hope this helps.

Yeah, (i have hard intercooler piping) and i did a boost leak test early on (finding one full rip in a connector, but i haven't done much fine tuning since then...Could even a small leak affect it in a buck? Fuel filter is an interesting idea, what are other symtoms of that?

Yea, some small leaks can do even that much. Boost leaks will cripple your car and make it run like crap. Just fix the leaks and see how it runs.

Fuel cut? If it's too cold outside maybe.

Nah, I don't think 10 lbs on the stock turbo can freak out the MAF to the point of fuel cut.

nicholasramos said:

Nah, I don't think 10 lbs on the stock turbo can freak out the MAF to the point of fuel cut.

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I'm not too sure about that. I got fuel cut on stock pressure (11 psi) when it was at or below 0 degrees F. But when it was that cold, the bucking would stick around even if the car was fully warmed up.

A small leak when cold can be a Big one. Tighten the piss out of all your intercooler piping if your running stock worm gear clamps, That fixed this issue in my friends talon. the stock rubber piping becomes to hard to seal with a normal clamp force. I'd say your leaking from one or more of them when its cold.

Haha, no worries about 0F, here in SoCal, it never falls below 50F. I'm gonna change my thermostat this week, just in case it is stuck open...I think boost leak will be next

nicholasramos said:

Yeah, (i have hard intercooler piping) and i did a boost leak test early on (finding one full rip in a connector, but i haven't done much fine tuning since then...Could even a small leak affect it in a buck? Fuel filter is an interesting idea, what are other symtoms of that?

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Mine had gotten pretty bad but would buck and stutter when trying to accelerate. Started off kind of mild and only happened every once in a while but got worse. You said its not doing it after it warms up though so I'm not sure if that really is the problem.

You should check for boost leaks again. Maybe something got loose from the previous time that you checked. It's a pain in the azz but im almost certain you have boost leak issues.

I would do the following in this order.

Check for boost leaks. Also check the plugs. Make sure you are using NGK BPR6ES plugs gapped to .028". If it's been a while since the wires have been replaced, you might want to do that too. A fuel filter would be good as well if it hasn't been done in a while, or you don't know the last time it was done.

Good luck!

Yeah I've got the ride NGK spark plugs and new wires too, I'll definitely do a boost leak check on a related? note, is gradual boost drop at WOT a sign of boost leak? I usually peak around 12, and then it may decline gradually to about 7 or 8 after holding WOT for a 5 seconds or so.

nicholasramos said:

note, is gradual boost drop at WOT a sign of boost leak? I usually peak around 12, and then it may decline gradually to about 7 or 8 after holding WOT for a 5 seconds or so.

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No, that is NOT a sign of a boost leak. Unfortunately that is the way it goes with that little t-25.

Yeah, I figured, its not a big deal, the poor little guy just can't keep up.

Resolved: So first of all, I took care of the fact that my GST wouldn't warm up for 10 miles by installing a thermostat (The previous owner must have felt it was unnecessary :/ ). Now that my car was at operating temperature after a few miles, I hit the boost leak tester, and Boy, it is incredible what a boost leak test can do. I feel like I've created a monster. No more buck, peaking 15 psi and holding 11 consistently! Thanks guys.