Thread: AC makes car die at idle

After finally installing the AC on my car (1.6 to 2.0 swap) when at idle the car will die. The car dies when the compressor kicks on. I can start the car with AC on and it will run for a few mins. I have a calum rt b14 ecu. The AC blows ice cold. I have no other idle problems. Any ideas are gratefully appreciated. I tried searching but AC is only 2 letters and didn't find anything under alternate terms.
Btw the AC was vacuumed pressure tested and filled with a professional machine.

the ECU idles up the engine when the A/C is kicked on.. somehow somewhere the Idle valve isnt getting that signal... might wanna get a schematic and trace that harness..

I would start at cleaning your IACV, as that's what controls idle dips when accessories drag power from the engine at idle.

When you power on your a/c it activates your ficv, that valve should definitely be cleaned out and tested to make sure it runs. Im not sure if it runs the since you don't have the factory Ecu.

Ficv, fast idle control valve

Is there any way to test the ficv? Also does it just let in x amour of air or is there some table in the bin that needs to be changed per some sort of AC signal?

Well if your ficv is working dead head the steering left n right if it don't shut off or idles rough its working.

Can't tell if idles rough due to s4s and no ps so it doesn't idle up. I have about 2 other iacv I will clean one and put it on but I just want to know if there is a way to test or more importantly if there is something in the bin file that needs adjusting. But as soon as the compressor kicks in at idle it falls straight on it's face.

Problem solved. After looking through the fsm you apply 12v to the ficv solenoid and listen for a click. Did this and no click. Bench tested a spare and it worked. After taking the one on the car off I noticed that it was missing both the spring and the plunger. Long story short swapped over the spring and plunger and it works great even AC off idle is noticeably better. Thanks for all the input guys again the dash saves the day.

no problem im glad i can help

Where is the FICV located and what part of the FSM has info regarding this? I'm having the same issue the cars idle dips when the AC is on when stopping or starting.