I'm sitting here on a Sunday morning and checking out this forum and I keep seeing post talking about how their car starts sometimes, won't start at all, works fine except in really hot weather or works fine except in really cold weather and so on.
Instead of addressing each thread as I was starting to do, I've started this thread so people can see a good website that explains this problem, troubleshooting this problem and how to render repairs.
Be sure to start with the "Quick Guide" and the clickable links like "symptoms" and "below" in step A and the other steps.
I hope this saves a lot of people a lot of frustrating hours like I wasted trying to solve this problem!

http://techauto.tripod.com/

http://techauto.awardspace.com/mainrelay.html