I just recently got this car. It was running fine. but after this weekend, its started to intermiterly idle low. On the high way or off idle it seems to be running okay, but when i come to a stop it sometimes drops to like 500rpm at idle it doesn't cut off though. If i feather the throttle a bit it will come back and thne just drop right back down to a low idle. but if i cut the car off and then restart it, it will idle normal again for a while.

 

Sticking/dirty BAC valve is the common cause. Also check for vacuum leaks and make sure the TPS is within adjustment.

 

thanks man, oh by the way the BAC is the big selnoid looking thing on the left side of the upper intake right?