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hey guys, i have a problem.. i dunno what it is, i dont kno if any1 can help me, but here it goes.

R32 Skyline

Rb20det

R33 Turbo

aftermarket fuel pump

fmic

stock Bov

3" Straight Pipe exhaust, Decat, no resonator, no muffler

remapped to run .9bar

No boost control.

Recently, Boost dropped to .7bar

I changed the Fmic cos my old one was damaged, No difference

CLeaned AFM (was oily) No difference

Cleaned and tightened intercooler piping, No difference

Changed all turbo vac lines, No difference

CHecked turbo for shaft play, it is perfectly fine

Out of curiosity, we put on a Turbosmart Boost T, the setting is 0, as in, the valve is completely closed.

The car HIT .9Bar and held it. BUT-

If i hit full boost (.9) in 2nd gear, and say, shift into third gear @ 7000 rpm, the boost level drops dramatically and takes time to re spool up...

before the response was pretty much instant, so something is still not right.

ANY ideas?

Im thinking along the lines of the wastegate actuator diaphram being faulty?

or maybe a turbo exhaust gasket leak?

any otehr ideas?

thanks guys-

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exact same as me and i would like to know to

I put a Turbosmart Boost T, the setting is 0, as in, the valve is completely closed.

The car HIT 10 and held it. BUT-

If i hit full boost in 2nd gear, and say, shift into third gear @ 7000 rpm, the boost level drops dramatically and takes time to re spool up...

before the response was pretty much instant, so something is still not right.

haha... hrmm, im going to change the wastegate actuator possibly on monday.

Ill PM you if it works-

PM me if u figure out whats wrong with yours too mate-

anyone else any ideas?

thanks mate let me know

Speaking from limited mechanical experience, when my car was playing silly buggers like this, with a boost tee, I ended up thinking it was leaking boost from a dodgy exhaust - replaced the V-band clamp and exhaust gasket, to find that the car was still problematic - it ended up being a severe blockage in the exhaust near the catalytic converter - if all else fails, I reccommend you check this out. I could be wrong, but hey it's a forum.

Speaking from limited mechanical experience, when my car was playing silly buggers like this, with a boost tee, I ended up thinking it was leaking boost from a dodgy exhaust - replaced the V-band clamp and exhaust gasket, to find that the car was still problematic - it ended up being a severe blockage in the exhaust near the catalytic converter - if all else fails, I reccommend you check this out. I could be wrong, but hey it's a forum.

no exhaust isnt blocked

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