Interesting S13 AC problem

[SCOOBYSHAG]

Hey guys I have a 91 S13 with an S13 blacktop motor. When I turn on my A/C my rpms drop about 3-400 rpms. Also when coming up to stop signs or lights and I take my foot off of the gas the RPM's drop off way low sometimes causing the car to die.

What is causing this?

As a side problem which may be related every now and then when driving around my car will automatically go into limp mode. I click on the A/C and it takes me out of limp mode. When in limp mode however the tach fluctuates as well as the motor between 1200-2000 rpms.

Any help would be greatly appreciated!

[Luke]

I would check the A/C wiring out. Too bad I never got to hook up my A/C on my SR so I can't help with details. Sounds like wiring to me though.