Hi I have a 2004 f150.I am having problems starting it when its wet outside,I crank on it for along time,sometimes it starts sometimes it doesn't.I ahave checked all the coil packs and crankshaft position sensor electrical connection,nothing seems corroded or wet,I also applied silicone boot grease to all the connectionsbut still have problems

When was the last time you did a complete tune up including plugs and wire set? Did you install platinum plugs when you did it? Also you might try cleaning your Mass Airflow Sensor. DO NOT use carb cleaner on it. You can buy a can of cleaner at your local auto store. ( it must say approved for Mass Airflow Sensor)

I have'nt done a tune-up I only have 60,000 miles,it doesn't have piug wires only individual coil packs

You might want to change the plugs anyway and clean the sensor. See if that helps.

. Remove and fully charge the battery. Clean battery and cable connections; afterwards, apply dielectric grease.

. Change the platinum spark plugs with the same Motorcraft plugs that came in the truck. Replace them at least every 50,000 miles.

. Change the fuel filter, if it has not been done in the last 30,000 miles. The fuel rail has to be fully pressurized, in order for the engine to start.

You might want to change the plugs anyway and clean the sensor. See if that helps.

OK I will try that,thanks.