why does my car stall when i touch the brake pedal

ok man, I did that and the car did not stall this time. and I re attached the vacuum and started it again and it seemed fine. my left tale/brake lights came back on but the right side is still not working. So with that vacuum line off and plugged it did not stall, is that booster bad?

Yes that is what seems to be the reason for engine stall.... The lights are another matter.

alright. Everything seems to work, i did turn on the hazards and it stalled as if I hit the brake. turn signals flash fast,but no bulbs are out. I thought the MFS was going bad and it may still be the issue on that end. Thank You for your help!

You may want to have this looked into a bit closer... The hazard lights should not have any effect on the engine!!... With the vacuum hose unhooked, the brake pedal will not travel as far as before, lights may not come on!.. This is a strange one for sure!.. Unhook and plug vacuum hose and try the hazzards etc..to see if engine still stalls, try all lights..

just did. I had everything on, with the hose disconnected and plugged up the hazards on, turned them off, then I tried them again and the engine stalled. The Voltage indicator needle was bouncing up and down with the hazards going then went back to normal position with them off. There is a bad ground in there somewhere,but never had engine stall with that. I've had this car a month...lol. I'm goin to try to see if the car runs with the battery disconnected. although it reads 13.4 VDC when running. maybe the Alternator is acting up