speedbump

I have a tempermental 2000 f150 that will not always start when the weather is warm and/or humid... I have NO problems in the winter, but as soon as Spring hits, this cycle starts over: I'll jump in my truck and attempt to start multiple times... it'll turn over-and-over each time, but not fire-up. Then, for no rhyme or reason, it'll finally start up.

I'm hoping someone else might give me input as to where I should go from here - suggestions on where to start looking. Again, it doesn't happen in the winter... just when it's warm/hot, moist/wet outside...

Thanks for your help, in advance!

dallyack

Had a Chevy Geo that ran like a top in the winter but had a hard time starting when humid or damp and when it did start it idled rough as hell for about 10-15 minutes. The answer was a cracked vacuum hose.

paidforFORD

Had the same problem and it turned out to be a bad fuel pump. Did it for 3 years before I found out the problem.