I replaced caravan's leaky oil pan after putting back together it sometimes won't turn over when it does it trys to start but dies right away and a relay clicks fast and won't stop unless I remove it.
it always started before
Please elaborate on "it tries to start". Do you hear a single, rather loud clunk from the starter each time you turn the ignition switch to "crank"? If the starter does crank the engine, try holding the accelerator pedal down 1/4". If it stalls at idle, there's a real easy fix for that.
Part of what you described could be due to a run-down battery. Check the voltage and be sure it's 12.6 volts, or be sure the headlights stay bright when you try to crank the engine.