This morning I started my 96 contour, zetec, 123,000,atx, and it started up fine but when it tried to idle it would die instantly. I started and revved the engine multiple times and every time it would die as soon as the rpm's were at idle. I had a cel on the was 1131(O2 not switching, lean), but the code had gone of earlier that day. I had also added a bottle of injector and intake cleaner to the tank the week earlier and still have over 1/4 tank of gas. After work I tried starting the car again and it died at idle again. After a few times of this it started to idle badly and gradually got a little better to were it was staying near idle, although idle was a little eratic. CEL has not come back on and it seems to accelerate fine. Idle is eratic in gear and in park. About a month ago I had a misfire with blinking cel, I was nearly out of gas and thought maybe that is what caused it but maybe I was wrong. I know it could be plugs, wires, or coil, but wires and coil appear to be fine but I have not checked plugs yet. Any help would be greatly appreciated.

96 contour bought at auction supposedly just needed a break job. Not to mention Air conditioner, Fan contol switch, MAF sensor, plenum chamber, trunk lock, new side window, and still going.