3 days ago car started up and while driving down the st. it warning! on 1997 Chevrolet Cavalier

Car had gas; would turn over; acts like it wants to start but won't. New fuel filter, spark plugs ( get spark ) put on. Can hear fuel pump. Fuses appear ok. Checked for any bad connections...replaced Knock Sensor continues to turn over and seems like it's going to start but doesn't. The car was starting and running fine before it prior symptoms. Tried auto scan and it reads "no codes found"...Any help? thanks.

Asked by for the 1997 Chevrolet Cavalier
I would check fuel pressure-Key on engine off should be 41 to 47 psi.
Next check fuel injector pulse.

Low pressure could be fuel pump.
No injector pulse could be cam/crank sensor.

A couple of basic things to check would be all fuses and spark plugs and ignition wires.