pressurizing to test for leaks...?

[RotaryDiagnostics]

Well, i been trying for about a month now to get my idle to stop bouncing. I thought i fixed it numerous times. heres whats been done.

Replaced throttle body
Replaced and adjusted TPS
Put new gaskets upper and lower minifolds
New air bleeds under secondary injectors
pressure tested and theres no air leaks that i can find with soapy water.
tried different MAP, AFM, and ECU

still the thing bounces kinda from 1000-1500. sometimes it will bounce, sometimes it will raise up, hold there. then flutter around a few 100rpm. hold again. bounce a little more from, 1000-1500. kinda wierd idle. dont know really how to explain it.

One thing that had me thinking its still a vacuum leak is, no matter how much i bleed the brakes. I still get no brakes pressure when the car is on. So i capped off the brake booster line, and that did nothing.

OK, so i the way i pressureize it is, i bought a cap at home depot for 2.5" piping and tapped it with a fitting for air tools. i put in on pre-turbo (i remove the MAF and put it on the intake) I then lower my compressor down to about 5psi and fill it with some air. i remove it after a few second becuase i dont want to damage the motor by forcing to much air in there. i cap it with my finger so air dosnt back out. I can hear the air running through the motor. but cant tell if that air passing through the manifold or excaping some where underneath the manifolds. all the air escapes in about 7-10 seconds. so im just thinking thats the air passing through the motor and coming out the exhaust...

so is there a way to have the air pressure stay inside to see if it leak that way?

[sen2two]

Well, i been trying for about a month now to get my idle to stop bouncing. I thought i fixed it numerous times. heres whats been done.

Replaced throttle body
Replaced and adjusted TPS
Put new gaskets upper and lower minifolds
New air bleeds under secondary injectors
pressure tested and theres no air leaks that i can find with soapy water.
tried different MAP, AFM, and ECU

still the thing bounces kinda from 1000-1500. sometimes it will bounce, sometimes it will raise up, hold there. then flutter around a few 100rpm. hold again. bounce a little more from, 1000-1500. kinda wierd idle. dont know really how to explain it.

One thing that had me thinking its still a vacuum leak is, no matter how much i bleed the brakes. I still get no brakes pressure when the car is on. So i capped off the brake booster line, and that did nothing.

OK, so i the way i pressureize it is, i bought a cap at home depot for 2.5" piping and tapped it with a fitting for air tools. i put in on pre-turbo (i remove the MAF and put it on the intake) I then lower my compressor down to about 5psi and fill it with some air. i remove it after a few second becuase i dont want to damage the motor by forcing to much air in there. i cap it with my finger so air dosnt back out. I can hear the air running through the motor. but cant tell if that air passing through the manifold or excaping some where underneath the manifolds. all the air escapes in about 7-10 seconds. so im just thinking thats the air passing through the motor and coming out the exhaust...

so is there a way to have the air pressure stay inside to see if it leak that way?