Starting Problems

My son has a 1993 Plymouth Sundance manual transmition. He got it stuck in a snow drift and it had problems staying running afterwards, especially when he would push in the clutch. Now it will not start at all. I have replaced the battery and that is working fine. But there is nothing when you turn the ignition. I am assuming that the clutch is failing to engage so that it can start any sugguestions? What can I do to test it?
I also have a 1985 Chevy Celebrity and a 1989 Chevy Van that will not start. They both have gas. And they both previously ran. The celebrity ran good and then today it just cranks but no starting. You can hear the fuel injection kick in but it just won't fire. You can also smell gas so it is getting as far as the carb. The same with the van. It ran perfectly fine and I shut it off and returned to start it again 20 minutes later and it too just cranks and no fire. Could it be the fuel filter in both cases? Is there something that I can check or do to find out for sure? The fuses are fine but I'm just not that up to date on these cars. I need help! Thanks everyone. Happy Holidays!

  doober

Do us (me) a favor. Break this down one car at a time, decide which one is highest priority and start over, one car per thread. Oh yeah, before you do anything else read this (http://www.car-forums.com/talk/showthread.php?t=2200).

  vwhobo