I have a 1997 dodge ram pick up. What would cause a cylinder to miss fire ? And how can I fix it. Do not see and spark on or around the spark plug wire

. Only use Champion Spark Plugs, properly gapped, on Dodge pick-up trucks. Replace them, if they haven't been changed in 3 years.

. Apply dielectric grease to the top electrode and porcelein portion of the plug.

. Replace coil, if the problem persists.

. Check engine compression and look for intake manifold leaks, in extreme cases.

. Examine wiring going to the fuel injectors. Breaks in the wiring (e.g. by mice) can affect injector performance and cause incorrect wave forms, which can throw a code.

Will a miss fire make you fail a emission test

Yes, since it causes the Check Engine Light to stay on.

What if I turn the engine off. Will it still fail?

It won't pass, until you fix the problem.