Just put in the new spark plugs and wires as well as cold air intake. Was idling roughly before and immediately after the install all seemed well. This morning it was about 10 degrees out and I fired it up. Very rough idle, loud ping noise, I guess that's what misfiring sounds like? Revs were up and down, once I'm moving down the road it's fine. Come to a stop light and the revs dip again feeling like its going to stall. Sound like an idle air valve problem? Just bought the damn thing and the check engine light was on for the catalytic converters. So I'm not sure if the CEL is on now for something else.