that sounds like its your problem, and if its a turbo that will cause a pressure drop, fix your exhuast leak, wheres your exhuast leak at? try looking at the hose coming from the manifold into the turbo check it right at the ehaust manifold check that hose thats probly what it is let me know

 

another thing that i noticed...as you keep the turbo kicked in i will lose boost PSI
i know diddle squat about turbos...is this normal..or not..

 

^^^no....just check all the bolts from the exhaust manifold to the head, manifold to turbo (turbine housing), turbo to downpipe. also look/feel around the manifold and the turbine housing for any cracks...it's pretty common in stock cast manifolds/old turbine housings. you will see black exaust suit around the area of the leak

 

i can check all these without removing anything right?

 

you might have to remove a heat shield to get at the manifold but nothing serious....come on man just go out there and do it[&o] git er done

 

yea... git er dun...... start at the bock and follows the exhaust system/turbo and check every joint for a loose bolt and retighten everything.... do the same with the intake