Oil or fuel in #1 runner

Since the injector is near the bottom of the runner - normally there wouldn't be any way for gasoline to be in the intake upstream of the injection point. Remember, the pcv vents the crankcase into the intake manifold. Over the years, oil vapors can deposit quite a bit of oil throughout the intake manifold - quite normal. Additionally, each time you crank up the car, especially when it's colder outside, condensate that has occurred inside the engine gets boiled off and it goes into the intake as well - water mixing with oil - creates some really yucky stuff. Most intakes will have some measure of that stuff coating their insides.

If you're not having any other symptoms - a little wetness in the intake probably isn't anything to worry with.

One thing to check is that sometimes coolant from the egr spacer can leak into the intake. Could that be happening? If so, perhaps one of your egr spacer gaskets has failed.

Have you pulled the diagnostic codes to see what they tell you?