1994 honda civic will not start. New spark plugs and new fuel filter. The car will turn but not start. I have replaced clutch safety switch as well. lots of good gas on the tank. main relay and fuel pump was just check and all is in good working condition same as starter, battery and alternator.

sounds like its a bad Clutch Safety switch you can try this and see if it works

DIY Clutch Start Switch Bypass Club

Called the clutch switch, or clutch safety switch. Buy a new one, buy used from a junkyard, or bypass the switch by connecting the wires together. Those are pretty much your choices.
Good luck.

It seems your ignition switch has burned out - verifying good starter operation was an important component in furthering your diagnosis effort. The ignition switch is really a relay separate from the ignition key cylinder - when it fails to send battery voltage to the starter motor, you'll have the no-start condition described.
See the Honda Ignition switch replacement illustration below.

Just for completeness' sake, here's the generic response of a mechanic to a vehicle's no-start condition:

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

Illustration courtesy honda-tech.com (from 1994 Honda Civic EX manual).

http://honda-tech.com/showthread.php?t=2577784

clutch pedal safety switch must be in place

if it turns over and you are sure there is spark the only thing left is fuel. Get a can of starting fluid and have someone spray it into the open air filter box while trying to start the motor. if it starts the problem is fuel pump and or fuel filter

Try taking spark plugs out and then turn engine over, if water sprays fron cylinders then the reason it overheadted was head gascet fault, but once water is removed and spark plugs re-fitted then it should start. hope not head gascet tho.

please tick box if helped

check coil or modulator! good luck

Try doing an ohms test on your fuel injectors. Sounds like 1 or 2 could be bad.

Try a honda civic forum online or maybe autozones free auto repair information site online. Check your fuel pressure, spark, timing and air flow meter. When was the last time the car was tuned up? Check air filter, fuel filter, spark plugs, distributor cap+rotor and the ignition timing. Check for loose or corrosion around and or on contact points of wiring ( power, ground, and your spark plug wires if theres any sign of wear or corrosion.) Make sure fuel is fresh and not stale from aging over time.

Next things to check are fuel and spark, remove a spark plug and with the wire attached crank the motor, if you see spark in the plug then it's not a spark issue and probably a fuel problem. If there is no spark could be bad plugs or wires, or distrubitor cap. To check fuel remove injector cover and crank motor, if there is no fuel coming out then check fuel filter, fuel pump.

Good Luck