The car was not started for about a week and this morning when I turned the car on the RPM start high at 1k and then after a minute it just went to 1.7k and would rev between 1.2k and 1.7k. I let the temp of the car raise and then did a little revving myself. The idle went to 1k again with temp gauge about 25%. I put the car in drive and started driving and in about 5 minutes the check engine lite came on. I pulled the car to the side and turned it off to check the oil. The oil was fine and after about 3-5 minutes I started the car back up. The idle is fine now between 500 - 700 but the check engine lite stayed on. I drove about 9 miles with the check engine lite. Before the check engine lite the drive idle was at 1k - 1.2k. So, what is going on with my car? thanks!