Batterie is good, gas tank is full, engine is turning smooth, but not starding up. My guess is a dirty fuel filter, or gas pump! engine has 245,000 miles

Fuel pump: The fuel pump is responsible for delivering fuel from the gas tank to the engine. If the fuel pump is not functioning properly, the engine will not receive the fuel it needs to start.
Fuel filter: The fuel filter is responsible for removing impurities from the fuel as it flows from the tank to the engine. If the fuel filter is clogged, the engine may not receive enough fuel to start.
Ignition system: The ignition system is responsible for generating a spark that ignites the fuel in the engine. If there is a problem with the ignition system, the engine may not start.
Battery: If the battery is weak or dead, it will not be able to provide the necessary power to start the engine.
To diagnose the issue, you may want to try the following steps:
Check the fuel pump: You can check the fuel pump by listening for a humming sound when you turn the ignition key to the "on" position. If you don't hear a humming sound, the fuel pump may be the issue.
Check the fuel filter: You can check the fuel filter by removing it and inspecting it for any clogs or blockages.
Check the ignition system: You can check the ignition system by checking the spark plugs and ignition cables for any visible signs of damage.
Check the battery: You can check the battery by using a multimeter to test the voltage. If the voltage is low, the battery may be the issue.
If you are unable to diagnose the issue, it may be best to seek the help of a professional mechanic.

Fuel pump may be failing. Check fuel pressure at injector rail. If pressure is good and stays good, suspect fuel pump relay may be getting weak.

You've already eliminated the spark plug & wireset, distributor cap & rotor.
Sounds like your car needs a tune-up, specifically, the PCV (positive crankcase ventilation) valve, and/of the EGR (Exhaust Gas Recirculation) valve.

Components checked/replaced during a tune-up are:
air filter
motor oil
motor oil filter
breather filter
fuel filter(s)
fuel strainer
PCV valve
EGR valve
spark plugs
spark plug wires
ECM or distributor cap & rotor
cabin air filter
transmission oil filter
transmission oil
engine coolant
check all vacuum hoses and lines

Troubleshooting the no-start condition - from the 1990 Mitsu Mighty Max Repair Manual:

Priority Action Part Type -- Cause
1 Inspect Battery -- Battery Discharged or Faulty.
2 Inspect Battery Cable -- Corroded, Broken, Shorted or Poorly Connected Battery Cable.
3 Inspect Distributor Cap -- Distributor Cap Cracked or Burned.
3 Inspect Fuel Filter -- Clogged or Dirty Fuel Filter.
5 Inspect Ignition Coil -- Faulty Ignition Coil.
6 Inspect Wireset -- Worn, Damaged or Faulty Spark Plug Wire(s).
7 Inspect Spark Plug -- Incorrectly Gapped or Fouled Spark Plug(s).
8 Inspect Starter -- Starter Motor Faulty.
9 Inspect Fuel Pump -- Low Fuel Pressure.
10 Inspect Solenoid Switch -- Faulty Starter Solenoid Switch.
11 Inspect Fuel Pump Relay -- Faulty Fuel Pump Relay.
12 Inspect Fuel Injector Pressure Regulator -- Faulty Fuel Injector Pressure Regulator.
13 Inspect Ignition Switch -- Improperly Connected or Faulty Ignition Switch.
14 Inspect Starter Drive -- Faulty Starter Drive.
15 Inspect Fuel Injector -- Dirty or Worn Fuel Injectors.
16 Inspect Fuel Pump Strainer -- Clogged or Dirty Fuel Pump Strainerat.
17 Inspect Engine Control Computer -- Incorrect Operating Information Being Delivered and Sent From The EEC.
18 Inspect Fuel Tank -- Fuel Tank Empty.
19 Inspect Carburetor -- Carburetor Flooded or Faulty Choke.
20 Inspect Distributor -- Worn, Loose, or Incorrectly Installed Distributor.

Could be a weak fuel pump with the strainer being dirty, the fuel filter could need changed or possibly a leak in the seam of the gas tank. Pay attention to see if it also happens when you make a hard accelerated left turn, or if it is less noticeable when your fuel tank is full. When your tank is full, look for leaks under the car. You should also check for leaks in the fuel line leading from the tank all the way up to the fuel filter. You might get a CHECK ENGINE LIGHT that refers you to the injectors. This most likely means they are thirsty for fuel and are not getting it in the regular amount. Good luck.

You probably have a submersable pump. If you have run the gas on below 1/4 tank for some time, you probably burned out the pump. Alway fill up 1/2 tank or more.

And with the mileage, it isn't unusual to replace the pump.

is there a service engine light on? it could be the lac. needs to be cleaned out,is there a miss?

Fuel filter is located on the inside frame rail under the drivers door and the fuel filter is located in the gas tank. Start with the simple and change the fuel filter first, but it is common for the fuel pump to burn out when the gas tank has run out of fuel, but since your engine started back up. Good chance that your fuel pump may still be good and your fuel filter may have pick up dirty from the bottom of the gas tank which is causing your engine not to get any fuel.
Thank you for using fixya and good luck

I agree with you that there is not fuel to the engine.Fuel pump can still work but not delivering fuel because fuel filter is dirty. To check if fuel pump is turning on, listen to the fuel pump for 8 sec for priming at the time your ignition key is at on position, not the start position. After that it will be off until you start cranking. Have a helper stand near the gas tank to hear the pump. If there is not fuel pump sound, then it is a bad pump. If there is pump sound then it is a dirty fuel filter.

From 53 reg onwards, diesel pump is under R.H. rear wheel arch, hidden by the plastic wheel arch liner. Older versions have combined fuel pump/sender in the tank (under R.H part of rear seat).
You should be able to hear a faint purr from the pump when ignition is turned on but engine not yet running.

fuel pump can be out or starter is going out turn key over and listen for click in tank for fuel filter to turn on