I believe the idle is supposed to bump up to around 1200 when the AC is on, at least mine used to, but now the idle doesn't change when I turn the AC on, stays at 700-800, and that causes it to stall occaisionaly in traffic if I'm not careful. What controls/activates the idle bump for the AC?

 

Are you sure the compressor is engaging?

 

The AC works fine, blows cold.

 

mine does the same also....and when it starts getting engaged (when it has worked around 20 minutes in traffic) the idle goes 800-900 not steady and then suddenly the car turns off!!!!
whats wrong?

 

on s5 rx7s its the bac that opens when you turn the ac on and causes idle to increase so it doesnt stall. i assume theres no other trickery on the 3rd gens. check your bac for proper operation. i believe there are a few threads in the 2nd gen section about checking and cleaning the bac valve - sorry i dont know much about fds.

my s5 vert does the same thing but its intermittent, wich leads me to beleive its a wiring issue... imagine that. an rx7 with wiring problems.

 

the el unit bumps the revs under a couple of conditions - off hand i think the fan control switch (position 3-4) is one of them, not sure about ac though...

 

I have to admit my ignorance; what's the "bac"?

 

That is correct, whenever A/C is on, fan on 3-4, lights on or defrost on. Also, FYI, idle is normally 750rpm and under high electrical load (described) it is 850rpm. Are you sure you simply didn't notice the change because it is so slight?