So this is happening.. Turbo related.

i was thinking the wastegate.... i dont have my car but im putting a fmic on when i get it back, so well see if that fixes it.
 
blow into the wastegate vaccum line into the wastegate. if it blows through, its ******. if it hurts your cheek and you feel like a retarded pufferfish, its not. also, it may be that the wastegate flap isnt lining up with the port internally on the turbo, that is what happened to me
 
Couldn't it also be ****** if it dosent open at all.. would produce no boost and still make you look like a retarded pufferfish if you blow through the vacuum line.
 
Check your clamps on your intercooler piping to make sure their tight... Also check your manifold for cracks and last but not least the Wastegate... I had a similar prob but it was due to a cracked mani
 
update:
forge wastegate actuator in, no change....:(
cant smell or hear anything as an exhaust leak, im thinking interfooler.....gonna put my fmic in on monday
 
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Second or third that your WGA is not the problem. You would overboost if it went bad on you. If you had that big of a post MAF leak your AFR would go stupid rich under load. I can't tell from the video how rich that is, but it doesn't look abnormal.

If it was that big of an exhaust leak at the manifold, you'd also hear it. It sounds like your wastegate is actually stuck open, so you are essentially a NA car now. You should see some boost creep at higher rpms of a couple psi though I would think.

You should be able to just reach down on the stem of the WGA and pull or push it back and forth to feel the wastegate open and close.

It could also be a completely hosed turbo, but I haven't really heard of that happening. Also, your compressor wheel would become a massive obstruction and your car would feel super slow. You could take off your intak pipe and just see if you can spin it with your fingers.
 
OR, you could probably have a stuck wastegate...
 
WGA broken normally means overboost.

Can it be something simple? like BPV stuck open? (or partially open) but i think i can hear the turky... so sounds like boost to me.
Or cracks/openings on your signal for the gauge, a vacuum will tend to close a gap, while the boost may push a crack open etc. and then display the big goose egg.

Is it a mechanical gauge or electrical? I had problems with my electrical one; bought a mechanical one, they are quick, I think that is what i like about em.
 

It sounds like he's spooling up just fine, if not a little slow for a GT25. I doubt the turbo is "seized".

Second or third that your WGA is not the problem. You would overboost if it went bad on you. If you had that big of a post MAF leak your AFR would go stupid rich under load. I can't tell from the video how rich that is, but it doesn't look abnormal.

If it was that big of an exhaust leak at the manifold, you'd also hear it. It sounds like your wastegate is actually stuck open, so you are essentially a NA car now. You should see some boost creep at higher rpms of a couple psi though I would think.

You should be able to just reach down on the stem of the WGA and pull or push it back and forth to feel the wastegate open and close.

It could also be a completely hosed turbo, but I haven't really heard of that happening. Also, your compressor wheel would become a massive obstruction and your car would feel super slow. You could take off your intak pipe and just see if you can spin it with your fingers.

If it is the turbo you'd be hearing it contacting the housing as it spins. Boost would also be super laggy, and you'd feel a difference in the way the car drives.

Looking at your other gauge, I'd say to check the grounds and sensor wiring of your gauges. Next, check all your intercooler piping for any leaks. The fact that I can hear your BOV when I shift tells me your turbo is not "locked up". To me, it sounds like you have a boost leak somewhere.
 
Mechanical, The wheels spins freely with no play in out or side to side, the only thing I can think of now, is the wastegate is broken, as in the flap no longer exists.
 
if you disconnect the wastegate you should be able to flip the little rod and hear the flapper hitting the inside.
 
Check your gauge to make sure its working correctly.
I was reading through this and watched your video and it looks pretty much the same as what my gauge is doing (looks like the same gauge as well). I noticed on mine however that when shut off it wouldn't go completely to zero and it was also occasionally showing some rediculous vacuum. So I decided to hookup a vacuum test gauge today just to check and found out my gauge must be shot cuz I'm running normal vacuum and I am actually building boost.
So time for me to get a new gauge I saw someone said mechanical is the way to go?
 
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