2003 Saturn L300 Won't Start

Starter fires over like a champ but won’t catch. Wife was driving and said when the speed increased on the hwy she pressed on the accelerator and the car started slowing down and finally stopped. No noises or anything that would alert. Had problems with A/C last week… would come on intermittently and then stop. Wife said A/C started working today like it should. I’ve done all the basic checks I know of… any suggestions?

You claim you have done the basic checks. So what is the fuel pressure reading? You have verified spark on all cylinders? What are the compression readings? Vacuum readings? Is the timing belt still intact? All of these items need checked first.

What basic checks? Do you have spark? Is the fuel pressure correct? Are the fuel injectors ticking? If all of these are good, have you checked the compression?