My vaccum at idle and while driving suddenly dropped. Have been boosting only 5 psi, car is tuned, B16a with a T3 Super 60 turbo

Does this mean I have a blown engine?

On nuetral when and idling its 14 in/hg, when i rev the car to 1500 to 2000 rpm i get 20 in/hg...

Any inputs?

 

Did you check to see if all of your vaccum lines are still attached? No cracks/splits?

 

Less vacuum at idle can be a few things. Its weird what your IACV can do if the idle portion of your map isnt just right. Say for instance, if the idle portion of your fuel map is lean enough to cause stumbles and an idle drop the IACV will open up until it comes back up. This will show vacuum in the 18-15's area in my experience. Broken ringlands will also pull less vacuum in my experience, haha
Also, bent/not seating correctly valves will pull less vacuum.
Let the car sit, and then go through a normal warm-up cylcle, and see what it does. If you blip the throttle will it settle at 20" for a second at idle, then stumble and swing to 15"?

Good luck.

This of course is assuming no vacuum leaks on your gauge or IM.

 

^^^
what he said :P
are you using a rubber hose or that plastic hose that comes with it?

 

I've checked my vaccum hoses and i couldn't find any leak.
For my gauge i'm use the plastic line from autometer then i have it inserted into a rubber hose and sealed tight.

I'll try bliping my car and see what happens, having a compression check also. wish me luck