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T3/T4 not spooling in first

Dunno what to say man. I'll see 5psi at 1800, 3500 it's sitting full tilt at 20 on the wastegate in any gear but I also have a converter to flash against. Even in locked in OD it'll see 15psi by 2800, takes a minute to get there though, and the revs climb kinda fast after that, along with the MPH...

But no boost in neutral right? I haven't had the chance to actually drive the car since the pcv incident so I'll possibly see the same results...? All I can do is pray... and perform more diagnosis haha :x:

What does the wideband say? I didn't see if you have a stock cam or not, which will affect vacuum at idle. Spray carb and choke cleaner at all the vacuum ports, if your idle raises you know it's a leak.

Actually still waiting on a new sensor for my wideband so will update eventually. I'm still on the stock T cam
 
Probably with working the throttle I could spool it up a few pounds in neutral, but that's a completely irrelevant test unless you're some dubber at an import show trying to vent the BOV to make yourself look cool...

Am I reading this correct that you're questioning a boost issue without even having driven the car? Flawed logic is seriously flawed...
 
Probably with working the throttle I could spool it up a few pounds in neutral, but that's a completely irrelevant test unless you're some dubber at an import show trying to vent the BOV to make yourself look cool...

Am I reading this correct that you're questioning a boost issue without even having driven the car? Flawed logic is seriously flawed...

Was just going off the recommendation that vacuum on these cars should be between 18-22mmHg. And mine is slightly lower than that cold.
 
You're right, but im still concerned now that someone has said that the vacuum line was there stock. Was blocking it a mistake? Makes no sense for it to be there to me, pretty much a built in boost leak.
 
You're right, but im still concerned now that someone has said that the vacuum line was there stock. Was blocking it a mistake? Makes no sense for it to be there to me, pretty much a built in seal destroyer, ring unseater, crankcase pressurizer-er.

You may want to find a vacuum line diagram.... and fix all the previous owners "fixes". My 245 had some great vacuum line "fixes"
 
You might be caught up in what other people are describing. You're still running an M46 which has a ridiculously short first gear that isn't going to load the engine well. Go out on the highway in 4th gear, punch it at 2k rpm, and record when it hits max boost.

On a side note: can you get pictures of how your wastegate signal is plumbed?
 
Can't get a pic but I can describe everything non stock I've done vacuum/wastegate wise.
To start, I have a vacuum line coming off the stock nipple on the manifold (originally used for internal wastegate on stock Turbo) which is split in 3 by a 3 way splitter (not a tee but like equal angles between each nipple like a 3 point star). Off that splitter I have a vacuum line going to the bottom port on my external wastegate and the other vacuum line going to the boost solenoid for my EBC (Greddy E-01). From that solenoid I also have a vacuum line running to the top port of the wastegate. And lastly I have the stock FPR vacuum line cut and split (using another 3 way splitter) with one line going to the FPR and another going to the pressure sensor for the EBC. Most of this was me just following the instructions for the EBC.
 
nobody suggested a CBV problem yet?
Is the engine using a CBV? is it actually working and hooked up correctly?
it should be holding boost while throttle is applied = boost pressure acting against the CBV valve keeping it shut
OR
letting boost escape when throttle is shut = high vacume in intake manifold. The vacume is supposed to pull the CBV valve open.
The signal hose should be connected to the intake manifold between plenum chamber and throttle body
If that CBV is not working then the turbo can spin like crazy but it still won't produce proper boost.
 
Brand/model of wastegate might help, to know if it's plumbed correctly...

But yeah, I'm with John. Have you driven it in it's current setup to verify there is a problem at this point?
 
To start, I have a vacuum line coming off the stock nipple on the manifold (originally used for internal wastegate on stock Turbo) which is split in 3 by a 3 way splitter (not a tee but like equal angles between each nipple like a 3 point star). Off that splitter I have a vacuum line going to the bottom port on my external wastegate and the other vacuum line going to the boost solenoid for my EBC (Greddy E-01). From that solenoid I also have a vacuum line running to the top port of the wastegate. And lastly I have the stock FPR vacuum line cut and split (using another 3 way splitter) with one line going to the FPR and another going to the pressure sensor for the EBC. Most of this was me just following the instructions for the EBC.

Don't use manifold vacuum for the bottom port of the wastegate nor the solenoid. They need to be a boost reference off the compressor housing.
 
Wastegate is an old model turbosmart evolution 38mm external wastegate. I haven't driven the car with the pcv vacuum line block offs yet but I am going to take those off anyways because they aren't supposed to be there. Might get a small check valve so that the vacuum line is only open under vacuum and not boost although I've heard the hose coming from pre-turbo should pull enough vacuum under boost to make it nearly impossible for any of the boost coming through the vacuum line to make it into the pcv.

I have no nipples on my compressor housing...
 
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