What did your gas gauge read while you were having issues, and did you fill it up before or after issue self-resolved?
If it does it again, check for fuel at the test port under the hood (schrader valve). Cover with a rag and depress center pin (like a tire valve). No fuel =no pressure = pump or clogged fuel filter.

When it started having the issue I'm pretty sure I had about 3/4 of a tank and had not filled up for 2-3 days. I replaced the fuel filter after the problem started and filled the tank the day after I replaced the fuel filter. Problem persisted. Another couple days went by so I added the Techron and filled up again. Since then, no more issues. But, before the problem went away, the car was getting spark and fuel. I checked this upon tune up. Plugs gapped to .040, ac Delco factory wires, copper core plugs, Delphi ects and AC Delco fuel filter. Pigtail for ects has power at the connector and everything. She's breathing well runs like a top for now so unless the problem persists, I'm chalking this up to dirty fuel system, bad gas or gremlins.

You may never really know what the problem was. Just be thankful that it's doing good for now and put a bottle of Techron in it every 10,000 miles or so. That's some good stuff!

Yes it is. Seed recommended it a while back when I was doing an mpg by octane comparison. I usually just put a bottle of the complete system treatment in as Winter arrives and again as Summer arrives. This time I just threw in the Techron injector cleaner. Hope that's all it needed. A little miracle in a bottle. I plan on keeping the car as long as I can. I take damn good care of it in and out. Tune up every 30k and regular maintenance as needed. I keep it clean. Hope to get 300k out of it. I'm just shy of the 200k mark now. I want to thank you and derf for the input. If it happens again I'll resurrect this post and go from there.

It's doing it again. Check engine light this time codes po336 and po141. Keep in mind I just replaced the cos and both o2 sensors already. So derf, you think I might be #11. Ecu? Ects and pigtail replaced as well. Happens after about 10-20 minutes after the car is parked after it's warmed up. I'm gonna try another cps in Case the one I got was defective. I don't know.

Where are you getting the sensors, Ken? If at Autozone, please get your money back and try at least NAPA. I used to work for the zone years ago and they sell the cheaper versions of electrical parts that are just borderline good. They've done some very unscrupulous things with vendors over the years which just added to the list of reasons that I quit working for them after 5 years of BS. I just got fed up with the way they were going and refused to go along with things that I thought were both morally and ethically wrong.

AC Delco crank position sensor and NTK (NGK) O2 sensors. Ects is a Delphi with factory replacement pigtail, NGK copper plugs, AC Delco wires, AC Delco coils, AC Delco fuel filter, AC Delco pcv valve all replaced after the problem started (due for it anyway). Also, I used dielectric grease where applicable. So, my new crank position sensor will be in by Monday at the latest. Keeping my fingers crossed. Didn't know if those tri codes in conjunction with each other would throw a red flag up for anyone here that may have had the same problem. Just keep ruling things out until then. I should replace the gas tank straps soon, think I'll look at the fuel strainer and pump next. The fuel filter I replaced was dissected by me afterward and it was awful. I had replaced it just 2 years earlier and you' swear it had been the original with 200k on it. So, I'm sure the fuel system could use some attention. I wouldn't be doing all this if I wasn't planning on keeping the car for at least the next 2-3 years, but that's the plan. After cps, if issue persists I'll go for the ecu and fuel pump/sending unit. I know nothing points to this except maybe ecu, as it's getting plenty of fuel and spark but hey, it won't hurt.

Oh yeah. Check engine light went out on its own upon restarting the car the time after it came on about 45 minutes later.

P0141 is for the rear 02 heater. The rear is just the policeman. does not affect air fuel mix.
P0336 MAY set after several failed attempts at starting, but I believe ONLY if there is a real issue with the CKP or its circuit such that at least one of the failed crank attempts didn't generate an acceptable CKP signal, thereby flagging the PCM to throw the code. Once the car has started up successfully, I'm sure there is a predetermined amount of time after which the PCM says all clear and the SES goes out.

Keep your scanner in the car. Clear the codes.
As soon as you fail to turn it over when warm, turn key to run and read the codes, If the CKP circuit is acting up, you should have a pending 0336.
Pop the hood and do the fuel pressure test I mentioned and recheck spark.

Never use anti seize around O2 sensors. They rely on accessing atmospheric conditions as a reference for their reading. Anything that can heat up and run may clog the hole through which the sensor accesses the environment.

As far as P0141, check the connector for corrosion and wire integrity. I'd tell you to check the heater fuse but since your SES turns off at times, the code is being cleared, which says to me poor connection or heater bad on the sensor (did you perhaps drop kick it in frustration?)

Lol... No dropkick and no antiseize. I used electrical grease on the plug boots/ends and around the edges of the coils only, just to keep water and corrosion away. The crank position sensor should be in at the beginning of the week. I'll check the lead to it but I cleans up all contact points where my sensors plug in. We'll get there eventually! Thanks derf and ruby.