Son-in-law did a tune up. Plugs, plug wires, rotor, distrbuter cap, pvc valve and all the filters. He change the oil also. The fuel pump was the original problem. He changed the pump and fuel filter. The first pump was bad and had to be replaced again. Now it will start but you have to pump the gas pedal. Yesterday it ran ok until it warmed up then died, then it would start and die right away unless it was kept revved up. Today when I just tried it I had to pump it and it would die right away and seems to be really rough. Jim Plugs

A normal tune up is plugs/wires/cap/rotor and fuel filter. If you have a DIS (distributorless ignition system) change plugs,wires,fuel filter. You can also change oil and air filter.

I have done the same above including seafoam and filter with coil, and still have the same issue. I'm thinking fuel bowl or pump.

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.

Thanks for choosing FixYa and welcome. For a tune up, you would need to change spark plugs, coils, distributor cap, coil pack, and wires. You would change the air filter and the fuel filter also. Change your pcv valve as well. You can also change all your fluids and filters, such as oil, coolant fluid, and transmission fluid.

Here is a list. Bad timing,dirty air filter,cheap gas,old spark plugs,bad spark plug wires,bad fuel pump,bad fuel regulator,bad exhaust system meaning full of holes,dirty oil and oil filter,dirty fuel filter.

This would include your spark plugs or coils, the wires, a new distributor cap, an oil change, air filter, fuel filter, and a coolant flush. A tune up can make a car run like new again. Some don't change the fuel filter on a tune up but I have always said it is best too. They can get clogged up over time.

Just basically spark plugs and an air filter. The plugs don't need replacement until 100,000 miles. The fuel filter is located inside the fuel pump assembly in the gas tank and is not serviceable. It doesn't require a PCV valve and there are no adjustments available for the throttle body, idle or timing.

I would change the spark plugs, spark plug wires, distributor cap and rotor, fuel filter, check and change air filter if dirty, check timing, check and top off all fluids, check or change transmission fluid, check brake pads/.shoes and drums/rotors for wear and check tire pressure, check the condition of all belts and hoses and replace as needed, check condition of radiator antifreeze and top off or replace as needed.

Do a quick check. Run a wire passed everything from the battery positive terminal to the power connector on the pump, or if you cant get to the pump directly then the first connection you can make to the pump's power supply wire. If she fires up then its a bad fuse, faulty relay or something electronic not putting the power through. If she still refuses to fire it could be the fuel filter filter (to lean), leaking fuel regulator or leaking injectors (too rich). the regulator has a vacuum line on it. If there is a leak in the regulator then fuel vapour is carried by the vacuum line and enriches the air in the intake manifold. The fuel pump has to deliver about 40 - 50 pounds of pressure to the fuel line and has to keep about 90% of that pressure for about 5 minutes after it has been switched off. Dropping pressure indicates poor valves on the pump or leaking injectors. It is not enough that the pump is effective the fuel line should be capable of filling a pint pot in about 15 seconds. If the pump has good pressure (and retention when off) but poor flow then the filter is clogged (this will also kill the pump eventually). As a final check make sure the idle air control valve on the throttle body is clean and functioning as it should.

Sounds like a fuel mix problem possibly the oxygen sensor. If it ran like this immediately after the new plugs, I would check to make sure all the plug wires are on the right plugs and secure. Good luck!