Idle Problem after changing master cylinder

[slokum]

89 240sx - automaticI have a problem with my idle, its kinda complicated. My brake light inside the car was on for over a month, which indicates low fluid, so i didnt have time to find out where the leak was so i just kept filling the cylinder. Finally i came out and there was no fluid in the car. So i determined the problem was the Master cylinder leaking, i changed it and fixed the brake problem, but when i drove the car after changing the MC, the car hesitated and would not idle After warming up. It did not do this right away it was after it warmed up. Over the past two days i tested this and verified it, the car has to be warm for this to happen, I thought it to be a vacuum problem and changed the TPS, Cleaned the AIV, changed hoses near egr to bpt checked all other vacuum hoses. Could this be the Brake booster causing this problem? from the fluid leaking inside for a month? Any ideas are welcome, i tried alot and dont wanna get ripped off from the dealer! And my other question does vacuum play a role in shifting a 89 240sx automatic? Thanks

[drjohn]

You can take the vac. hose off the booster and plug the end to the eng. and start the car and see how it runs. Do this after the car is warm. The brake fluid running out the back of the master cyl. may have damaged the seal in the booster.

[slokum]

Thanks for answering ..... yea tha tis what i figuredm but thanks for the tip , ill give it a try and let everyone know, ........ did you know about the shifting and vacuum piece?