i have a 91 CRX HF w/ a Z6 swap in it...the problem i have rite now is when i step on my brakes..the engine will almost stall out and the rpm drops below 500..but when i let go of the brakes it will act normal..u guys have any ideas whats causing the problem??

 

check your vacum lines.

When my master cyclinder was going out, i was having this problem. Vacum related.....though it got to the point where i could hear a shoosh of air everytime i hit the breaks.

 

Defienately sounds like a vacuum problem..Check the vacuum line(s) that go to the master cylinder..

 

i'll check on that....thanks

oh yeah..u think i should replace my MC to the Si, I upgraded to the EX/Si front knuckle, rotor, and calipers. i also plan on doing the rear disc conversion..but not anytime soon

 

well i checked the vacuum on the booster...i blew out the hose and the check valve..but it still does it??