put in park rpm went up 20 without pressing the gas then i put it in gear and shifted hard?
Check engine light should be on, have the vehicle scanned for codes to pin point the problem. I suspect the Throttle Positioning Sensor and or a broke wire at the plugin. A code of p1515 to p1519 would show up if I am right.
sounds like a throttle body issue. can you press the accelerator hard at idle (just step on it quickly...) and the idle comes back down? Try shifting if yes to see if the hard clunk into gear is gone... if no, you may need something as simple as a throttle body cleaning to get the carbon build-up removed. Just a good place to start. Have a pro do it if you're not comfortable picking up cleaner at NAPA or another auto parts store. (take a look at your air filter too. Ask to see a new one out of the box if you're unsure if you should replace it.)
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