IAC VALVE
 

I have a 03 mustang gt and just wanted to know if the car is suppost to shut off when u unplug the idle air control valve???? IAC??? PLEASE LET ME KNOW ASAP THANKS GUYS

Well... yeah. It's the idle air control. If it can't fix the air going in at idle, then the car might stall out due to being starved of air.

That's not to say a pristine throttle body might not let air in enough for it to stumble about trying to stay running, but a dirty throttle body might spell curtains.

So... I'mma go with maybe... and also ask, what's the need to know? Why are you disconnecting it?

Im trying to see if the sensor was good ive been having a problem with my stang when it hit normal opperating tempature it wont go pass 3500-4k rpm and it feels like a rev limiter!!! It does it every gear u put it in 2nd and its hella strong till it hits the rpm i mentioned im stuck i need help

Try a fuel filter first.

I WAS THINKING OF DOING THAT AFTER WORK ILL KEEP U POSTED IF IT WORKED OR NOT THANKS! :)