HELP NEEDED: Engine racing & gurgling

[Daytona]

A little background first... Car is bone stock with 71,109 miles on it. Regularly serviced professionally (last oil change was 2 months ago). 1 gallon shy of a full tank of gas (Regular 87 Octane). 3.4L with auto trans. Weather is unusually cold today for mid-April (low-to-mid-40's). Park in my driveway, slanted downhill towards the backyard, with the nose facing downslope.

Was out doing errands today with the g/f. Nice casual ride home. Nothing experienced out of the ordinary. But when I put it in park in my driveway something didn't sound right, but I shrugged it off. 5 hours later I go to move my car and the engine starts racing. Cold idle is usually 1000-1100 rpm, but now it's 1300-1500 and I could hear something rough-sounding that I've enver heard before.

I rev the engine a few times and it's still sitting unusually high. I shut it off and hear what can only be described as fluids gurgling. The gurgling lasted for over 5 seconds after the engine was shut. don't recall ever hearing that before either.

I wait a minute and then restart the car. The engine races again so I leave it on and pop the hood. Nothing seems out of sorts and I even check the oil dipstick just in case the oil's low and the engine's trying to compensate or there's a blockage somewhere. I manually start pulling on the throttle cable and it's revving up fine but not sounding like it's settling. Worse, each time I release the cable I hear something tap under the intake/valve cover.

I try it a few times with the same result. I shut the hood and then shut the engine. The gurgling occurs again. Restart the engine it idles fine now. Took it for a drive on the highway 1 exit and then back. Do an even 55mph one way then race it quick to 80 in the other direction. Everything feels and sounds fine.

I get home and she's idling fine. I shut the car off. Same gurgling.

WTF?!?!?

Anyone with any experience with this and know what this might possibly be? Not interested in hearing wild guesses. But if any of you have actually dealt with this specific issue I'd love to hear from you.

Thanks!