Idling high out of nowhere

Please help! I have a ‘94 V6. Driving yesterday, it started idling at 15 to 1600 RPMs. Had to stand on the brakes hard at traffic lights just to keep it still. Even got to the point where the temperature got extremely high. I know there are other topics on the same thing, but I am so lost with all the different possibilities. It is not bouncing but staying steady at a higher RPM. This wasn’t happening two days ago. Can anyone help me?
 
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On my 91 5.0 with all clear codes, a suggested hanging idle fix is cleaning the tps connectors. I will also be testing it with a meter. I figure the computer system is not so different in your V-6.
The high temp thing may be a clue. Have you run codes?
 
I had that exact thing happen on my old 94 V6. Turns out the idle air controller (IAC) malfunctioned and kept letting in air while the engine was running. Try unplugging it and see if that makes any difference. If you're not sure what the IAC looks like or where it is, search for "iac 94 mustang 3.8" on google, and click the Images tab.
 
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