ive searched and cant find a solution to my problem anywhere. i go out to my car today and try to start itand it wouldnt start it was trying to but as i tryed the cel lit up and the d4 light was blinking but a soon as it started up after a few more attempts it ran like normal. and now everytime i start it up the d4 light comes on for a second when its in park but then goes off. my car also has a really low idle these days can anyone help me with these problems please?

