Misfire 2004 Mercury Sable. Codes P0303 305, and 316 and the check engine light on.

Question

My car misfires and runs rough every time it rains. The auto place tested it, and these are the codes they got. P0303, 305, and 316.Any ideas what it may be ? Coil caps ? They told me that the 316 code is a misfire on start up. What would cause that ? I have the intake off now to get to everything. It doesn't have a coil pack. Just individual coils to the plugs.

Answer 1

Hi there,

Since it's happening when it rains, I would start by replacing the coils on cylinder 3 and 5, then clear the codes and see if they come back, especially the 316, you may also need a coil on that one as well.