89f150wv

1989 F150 4.9efi will crank and crank an crank but will not fire up if its wet out such as rain or snow., give it a day or hours later if your lucky., for it dry out enough and it will fire right up. any ideas what this could be?

88xlt

I would be inclined to inspect inside under the distributor cap next time it won't start. Or just go ahead and replace the distributor cap anyway. The cap sometimes just get a crappy coating inside them and the only cure is to replace the cap. This may not solve your problem, but it's the first thing I would try.

Ol' Blue ohio

Would also be my guess might want to do a tune up on it. Replace cap, rotor, plugs, an wires. Try shooting some wire drying agent on the wires an see if it helps.

95SWB

My dad has a 93 and for a long time it wouldn't run when it was wet out. He called it F#&@edOnRainyDays but we eventually located the problem after changing many parts as previously suggested. Where the hood meets the cowl on underside there is a hard plastic drip cap. If you follow the drip cap towards driver side you'll notice where it stops, directly above the pcm firewall connector. One day it was raining I sat out with the hood slightly lifted up and watched the water drain directly to the computer. We made a rubber cover and silicone it to firewall. Been near 5 years ago and its not been an issue and all components are good. I'll see if I can get some pictures next time I see him.

mobrien8831

I'd bet the ICM...had same issue for along time then it shut down on me...any codes?

95SWB

It never threw any codes, if it was wet no go and if it was dry just fine. I'll be there tomorrow and take some pictures of how we fixed it.