Have to wait for it to cool off? Probably ECU. Located behind washer fluid on firewall. GL
Unmetered air sneaking in to the intake. Look for vacuum leaks.
spark plug
yes Engine is wearing out.
Could be several things, First try a few shims between the engine and the starter, if that doesn't work, change the starter. Just a suggestion.
Valves tapping?
Does it have enough compression?
is the van getting spark? does the fuel rail have fuel pressure Might want to check your knock sensor if equipped
I'll tell you what, my husband has an 88 Ranger and I am on this site to find out the same exact answer! We even replaced the alternator, and still, no spark. Isn't it weird?
Without year make model & engine size you get a guess. Ignition module, coil, distributor
ON MY 3.8 IT WAS A SPARK PLUG WIRE THAT WAS SHORTING TO THE FIRE WALL. HOPE THIS HELPS. PAUL G
Check the fuel line to see if it is pinched or otherwise leaking. change your oil. is your car revving unusually at startup?
If sit has a carb. perhaps choke is not releasing fast enough - causing it to run too rich until warm up