After Cold start engine runs rough. Vehicle may stumble, buck and shutter on initial acceleration. Engine may install at idle when transmission is is shifted from neutral to drive.
If the light just flashes then there is a problem that could damage the three way converter. If it stays on then there is a problem that could lead to a degradation in emission system. Perform a MIL fnction check and look for codes in the ECM or TCM.
It could be anything causing it. You will need to take it in to know for sure. There could be a short in the electrical system. Take it in and have it checked.
