2001 Chevy Prizm Engine won't start

Next time it refuses to start-don't wait for nothing-what you need to do is determine if its a fuel or spark problem that's preventing it from starting-Do below:

Get a helper disconnect a sparkplug wire or 2 and ground it to the engine atleast 3/16 away from ground-have helper crank engine over-do you have a snapping blue spark? If so-you have a fuel related problem, check the fuel pressure to rule out the fuel filter/fuel pump/pressure regulator and listen to the injector/s are they pulsing or hook up a noid light. No snapping blue spark continue to troubleshoot the ignition system-power input to the coil/coil packs, coil's resistances, cap and rotor, distributor pick-up coil, ignition control module, cam and crank sensors and computer Note: If it doesn't apply disregard it.

See if it's throwing any codes. Have it scanned for both soft and hard codes. You need to tell them you need both, otherwise they'll only check for hard codes mainly by looking at the Check Engine Light on the dash. If it isn't on, they'll say no codes present. Soft codes won't set the CEL.

Our reference shows the pressure regulator on the fuel rail.