I have a 98 150, 4.2. Now this sometimes happens when I'm driving in rain or even if it raining at all. But when there has been a heavy dew at night is all it takes. I start my truck early in the morning and it spits and sputters for about 5 minutes till it warms up ( sometimes takes longer ). Ive looked for water leakage under the hood and found nothing. Im suspecting the coil pack or the cam position sensor may have a crack in it but what do you fellas think? Makes my check engine light go crazy.

 

Have you had it scanned to indicate what code the CEL is sending?

 

Wet Wires?