You can pull a coil out and have someone crank the car. Check for spark to an engine ground while cranking. If you don't have a spark tester you can use an old spark plug or plug a screwdriver plugged in the coil. Don't get shocked. If you have a scan tool, check for an RPM signal for me and check codes. If not, the spark test will do do for now. Also check to see if the check engine goes out while cranking. If you have no spark unplug and plug back in the crank shaft sensor and see if it will start. It is located by the a/c compressor. Wiggle around the wires going to the connector. Do that and let me know what you come up with.
Don't replace the oxygen sensors for rich codes. The codes mean you have a rich condition, not bad sensors. If you didn't reset the engine computer after doing all the fuel system repairs, do that and see if the light comes back on. Disconnect the battery cables a while to reset the computer. If you didn't have rich codes and just have a pair of lame O2 sensors, do replace them. Also check and make sure you have vacuum going to your fuel pressure regulator. Also make sure the fuel pressure is not running too high. Should be around 35 psi at idle. Need to check the engine coolant temp reading and throttle position reading. When its cold, temp should be around ambient, tp should read around 0.5 - 0.9V throttle closed.
I think your no start problem is caused by the crank sensor or wiring going to it. The cars symptoms sound just like this problem. I have a lot of intermittent no starts on these vehicles caused by this. Next time it won't start try wiggling and unplugging and plugging that connector. If it starts after that you ll know thats your problem. Sometimes just replacing the crank sensor will fix it, sometimes it also needs the connector.
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