How do you turn down the idle on my car it is up.

The idle is controlled by the pcm. Check mil codes, you can check those, yourself. Check and clean the idle air system.

Just to add, to check for mil codes, you use a jumper wire between the A & B terminals at the datalink connector. Turn key just till the dash lites come on, no further. Then, the mil on the dash starts flashing, you count the flashes to get the codes.

Also, Check and make sure the throttle valve is closing, as far as the idle.

Did you check for applicable mil codes? The iac valve is on the throttle-body. Clean the throttle-body. See if the iac has any gunk on it, clean it.

If nothing I'm saying makes any sense to you, then, I'm not sure how to help?