Idle speed set too high most likely. Also could be carbon deposits inside cylinder. There are a few other option, but the cheapest to check and fix is idle speed.
water in the fuel can cause an idling motor to sputter and/or die.
my 1990 300zx is idling rough what could cause this?
an egr valve stuck open would cause this, i cant remember for sure if this engine has one or not though. more likely is secondary ignition problems(i.e. cap,rotor,plug wires,or plugs)
Yes, it could.
old fuel filter
The radiator cooling fan is most likely not working.
Plugged fuel filter
Fuses
no
The most likely cause of a 1992 Ford Aerostar stalling while idling is bad spark plugs. The plugs should be changed and the timing checked to resolve the problem.
Could be your timing belt.
air leek