When I start up my car everything is fine. However, after I go for a drive and I go to park, when I put my car in park it will keep revving up and then back down. then up and down again in the same manner. It will keep doing that until i turn the car off. What could this be? Easy fix? Big problem or minor?

 

Check the IAC and FITV. There is a how to at the top of the page in the 'Accord FAQ'.

 

I'd also check the coolant level.