howdy. im pretty sure what is wrong with my car. when i drive with the car all warmed up the idle screws up when i brake/come to a stop, the rpms dip way way low. at first i thought this to be a bad egr because i had the same problem with my 240sx. then one day i drive without radio and instead of rpm dipping to 0!!! it only dipped to 300. i experimented with different electrical items on/running and i find that the ammount of electricity being used has a direct effect on how low the rpms dip. it must be electrical right? alternator maybe or grounding? btw when i sat in parking lot i turned everything on and idle dipped, then i turned everything off it idle back to 800. please help me before i get to the stalling stage!!!!!!

 

BAC valve.

 

the valve-looking thingy on the left side (as viewed from sitting in the driver's seat) of the throttle body (top of the engine)...Is it even there? Should have a small black coolant hose on each "end", and one connector on forward side...I figure if you didn't know that component controls your engine idle under load, I'd make it a little easier on ya...

 

this is the same on the 90 gxl too?