Isn't my brake booster supposed to hold vacuum?[RESOLVED]

[brownfinger]

My fuel trims keep maxing out to 140%. All of them. No intake or exhaust leaks, and I've tried about 4 different, new o2 sensors, new coil, new everything just about. This results in poor milage and cold driveability, plus sagging performance. The car runs perfect if I reset the ECU, but soon enough, the trims end-up maxed-out again. Having run-out of reasonable things to check or needlessly replace, I hooked-up my vacuum pump to my brake booster to see if it holds vacuum. It appears not to.
My question is simply: Am I correct in assuming that it is supposed to hold vacuum? I think I should know this before I go taking apart any more stuff to check it. I could plug the port and go drive it around with the logger hooked up to see what happens to my o2 trims, but that seems sort-of dangerous.
Anyone know?

 

[force_feed]

yes it should hold vacuum.

 

[95'RS-T]

i agree it should hold vac maybe its clogged somewhere id take it off and check it for a clog.

 

[Bud92gsx]

There only supposed to hold like two brake pumps after the car engine is shut off right?

But yes It should hold vacuem..

 

[brownfinger]

I just pulled the hose off the I M, and hooked up the pump there. I'll have to take the entire hose off and check at the booster. I'd have to hire someone else to kick my own ass if I were stupid enough to replace the booster, only then to learn that there was a hole in the hose.