I have 1994 f250 with 5.8 an sometimes it wont start, espically when it rains, i know its not my battery cables cuz i cleaned an checked them. i also replaced my battery clamps. my battery has plenty of juice an my starter doent make any weird sounds so i dont think its that, i thought it could be my distributer cap wasnt firing right but it starts sometimes and runs smooth when it does so i dont think it is that. Could it be module causing it not start? because its usually in rain when it doesnt start, i would appreciate any advice. Thanks

 

When it doesn't start, check the disty cap for moisture. Have you checked each plug to make sure you're getting spark?

 

Yeah if it won't even try to fire it's likely an ignition issue. As mentioned above, try checking for spark next time it refuses to fire. Grab a spark tester from the auto parts store, or starting fluid can be used to check for spark too but don't overdo it. A little bit is all you need.