Hello everyone. My car was recently idling and dying at stop signs and red lights a few weeks ago; and sometimes would not even stay running. My friend ran a test with a handheld computer and noticed that I need a new Idle Air Control (IAC) Valve. I have a 2.4 Convertible, so that piece costs about 300.00 at AutoZone. My good friend "ebay.com" gave it to me for 75.00 lol :)
So my friend installed it for me but now it's running very rough. My throttle body is very clean. The car now stays running and normal RPM (Between 5000 and 2000 RPM) I drove it and does not die anymore. But it's just running really rough and my engine shakes like crazy. My engine light came on while testing driving it and had it scan and the guy told me to check the "timing on the car"... What the HECK DOES THAT MEAN??
Please help!!!!!!

Thank u