Won't idle on its own. 02 Impala 3.8

Have an 02 Impala 3.8. Had been running fine then when running errands, seems like every dash light came flashing on once and the car stalled out a couple times when at low rev.
Fully charged battery. Can start the car but requires a push on the gas pedal. Car runs fine as long as my foot is on the gas. Warmed up I can manually idle at 7-8000 rpms with the lights, rear defrost, radio and full heater on. Not even a chug. Idles fine.
Dash voltage gauge reads mainly 13. Can even let idle drop to about 5000 rpms before voltage gauge starts to drop. With everything on.
If I take my foot off the gas at anytime the car dies. Not a sputter. Doesn't even try to stay running.
Am thinking its not alternator or battery but a sensor.
Any suggestions?

Am thinking its not alternator or battery but a sensor.

Did you actually test the alternator and battery?

Am thinking its not alternator or battery but a sensor.

Did you actually test the alternator and battery?

No. But I had everything on that could be so there would have been substantial power draw. No changes were noticeable as each one was turned on.

Can we assume this is a 3.8 Buick or corporate engine, if so, the egr could be stuck open, the iac not functioning, some kind of vacuum leak, all can cause the engine not to idle on it's own.

Just edited post.02 not 92.lol.
3.8 Impala.
Have to love/hate when this happens. Had it running numerous times today checking the battery/start, alternator functioning. Worked great til I took my foot off the gas.
Decided to warm it up good to clear the car off from the storm and after about 20 mins at manual idle, I let it die. Scraped the windows. And car started and idled on its own. Took for a drive, restarted multiple times. Like nothing happened.
Just a sign I know. Hopefully work thru Christmas.
Would the iac trigger a code? No codes were triggered at all. The egr would likely trigger one?

May be a pending code, it could take few faults before it would set a code.

Fully charged battery. Can start the car but requires a push on the gas pedal. Car runs fine as long as my foot is on the gas. Warmed up I can manually idle at 7-8000 rpms with the lights, rear defrost, radio and full heater on. Not even a chug. Idles fine.
Dash voltage gauge reads mainly 13. Can even let idle drop to about 5000 rpms before voltage gauge starts to drop.

8000? 5000?

hope that's a misprint of an extra zero......

Check the usual suspects....fuel in vac line to fuel pressure regulator.....see if it runs better with MAF disconnected......could be intermittent problem with IAC, either the valve or the connection at the harness...

sounds like you had a temporary clog in the cat.

sounds like you had a temporary clog in the cat.

Sorry should have updated. You may very well be right. Spent most of day manually keeping it idling and when I went out after supper, it started and idled on its own as if nothing had happened and not a problem since.