Give it a good cleaning. A quality induction system cleaner will include an aerosol can that (after removing the intake tube from the throttle body) you should spray onto the throttle body butterfly. If that solves your problem, sweet, it was a cheap fix. If it comes back within the next few days, I would assume it's your IAC motor.
How is your throttle response when driving? Do your revs fluctuate all over the place when you're cruising (staying within what SHOULD be a relatively constant rpm range)? If so, sounds like it might be a throttle body. Does it run rough in addition to your RPMs jumping when it's in park/neutral? That might indicate injectors being clogged. If that's the case, that induction cleaner I mentioned can help. Get yourself a kit that includes the aerosol throttle body cleaner AND a fuel additive to clean your injectors.
Hope this helps. Visit
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