When i turn the a/c on when idling the car shut off

Idle up valve needs checking manually.

Problem With Idle Air Bypass Valve May Cause Engine ...

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If you experience difficulty starting the engine when cold, stalling at idle, ... Also, this summer electric locks stopped working and recently car seems to idle high whensitting or when I put heat on. ... I was either braking and barely moving in traffic andwhen I would also turn on the ... 2004 Mercury Sable- 3.0L V699,000Visitor.

03 MERCURY SABLE ROUGH IDLE CAUSE - YouTube

I suspect that the idle solenoid in the carby is not shutting off the fuel through the idle circuit and so the engine is running on. Check it out that it is actually shutting off when you turn off the key

check your vacuum lines

is this a ford ? . try cleaning the iac its on the top of the engine and easy to get to .and let me know how it works

SOUND LIKE IDLE SPEED CONTROL.ENGINE IDLE SPEED TOO LOW.SCAN IT CHECK FOR FAULTY IDLE SPEED CONTROLLER.

it sounds like its drawing air into the inlet mannifold

Yes your choke is sticking

Check either the throttle position sensor, or idle air control valve. One or the other is the most likely culprit. Could also have a vacuum leak which will cause a high idle.

Trying disconnecting the battery again this time for 10 to 15 minutes. Then reconnect and see if it clears the problem.