why would a car idle just fine with the a/c on but shut off when ac is turned off?
When you turn on the AC the car will increase the idle to compensate for the extra load on the engine. Cars with a carburetor have a solenoid that opens the throttle more to keep the engine from stalling. Fuel injected cars will increase the opening in the idle air solenoid to keep the engine from stalling. My guess is this is working correctly on your car but the basic throttle setting is incorrect. I need more information to help more.
Search Mitsubishi Eclipse Spyder Questions
Mitsubishi Eclipse Spyder Experts