92 Sidekick will not start, have changed fuel pump, fuel filter, rotor, distributor cap, oil and air filters. sometimes out of the blue it will start but next time no! help!

fuel pump and filter

crank shaft position sensor

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.

sparkplug wires?

likely fuel pump, dirty MAF sesnor or distributor CMP sensor going. go here

http://groups.yahoo.com/group/villagerquest/

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.

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.

Replace the pick up coil in the distributor,this is the problem.

So you threw parts at it. No harm intended. Should have started with the adding gas part first. You know the filter is new and it does run! Are the fuel pump amps correct,pump mech bound,no fuel volume, pressure regulator work correctly? Does the pump run in start mode or time out? Now the harder stuff. What does the spark and timing look like,What is the computer seeing and then what command is it sending?

Once you rule out some kind of ignition problems,; spark plugs and wires, ignition timing, distrib. cap & rotor, the cause may be low fuel pressure from a failing pump or clogged filter. Listen to the pump in the gas tank. If its been getting louder lately, have the pressure tested.