Earlier this winter, the engine light came on upon startup for about a minute. I didn't think much about it because it went out and didn't come back on. Brought the truck in for a service last week and asked them to check the codes. They did a quick scan and found something amiss with cylinder #3. I brought it back today for a more in-depth scan and they told me that they are going to replace the coil and see where things go from there. From what I can understand, there is intermittent firing of the plugs. Nothing really stands out as far as engine noises, but my gas mileage this winter has been brutal. I'll provide updates as things progress.