funny noise when its hot or i am @65 miles/hr plus

[explondwa]

Hey all , please help, i have a 1992 explorer xlt and on and off when its hot outside and i'm going 55 per hr i start hearing this funny noise that sounds like a high pitch alarm like sound coming from the engine , this weekend it happened three or four times and even happened when i was going at 45mph the check engine light does not come on and the noise only goes away when i stop ,switch the ignition off and switch it on again , the first time it made the noise was when i was driving up to the mountains and i thought i'd accidentally hit the alarm button on my keys . is my egnine overheating or what is happening ? any advise will be highly appreciated.:redexp:

 

[yob_yeknom]

Idle Air Control (IAC) valves are known to make some weird noises sometimes. They've been discussed many times. Do a search and see what you come up with, maybe it'll be what you're looking for.