I am sure you are familiar with the fuel slosh effect mentioned here:

https://www.gmforum.com/lesabre-182/...-turns-302755/

Usually if the fuel pump loses power, it doesn't usually start right back up right away. It doesn't have fuel pressure on tap, so it takes a few seconds for the computer to fire the pump back on again.

Shutting off like that could be crank sensor, like already mentioned, or something ignition related, like an ICM, etc.

as she said she replaced that stuff. i like smokes idea. try looking for any grounds that may be intermittent take them off scuff them up with a wire brush and reassemble with dielectric grease

Yes, I have read up on the fuel slosh thing; loose baffles, etc. Since it is such a quick cut-off, I am leaning more towards the problem being related to ignition lost; possibly the ECM turning off the ignition in relation to a lost of signal such as an open or shorted wire.

My sister had a Pontiac that would suddenly take a nose dive while driving; I checked the TPS and found an area that would open up but was fine on either side. While driving if she press the pedal to move the TPS to that area, the TPS signal disappeared.

It may well be a wiring issue; if you read my past posts, I did find some bad wiring on the ICM harness and ended up replacing the harness.

These problems can be a real pain in the a**.

I should have added that my engine dying was identical to yours. Usually at slow speeds (15-20mph), moving along in heavy traffic situations. The engine was just there once second, and gone the next.

This is what I replaced before I made the engine stutter by twisting wires and found the problem: [ALL Delphi, AC/Delco parts]

MAF
IAC (3 of them!)
TPS (2 of them)
EGR valve
All new pigtails, IAC, EGR, MAF, TPS
Temp sending unit
Air temp sensor
New wires
New spark plugs
ICM
PCM (two purchased)
3 Coils
UIM and LIM gasket replacement, elbow
O2 sensor
New vacuum lines

I'm sure I'm forgetting something.

Since then I developed a misfire after warmup and a P0341 cam/crank sensor code. So back to buying...

Cam sensor
Crank sensor
Pigtails for both
Timing chain/tensioner
Sprockets

It ended up being the new Delphi ICM. Put the 17yr old ICM back on and fixed it.

The first list was all due to an intermittent TPS ground wire. The second because I believed the code. I definately feel your pain...

I decided to go ahead and order the new ACDelco fuel pressure regulator as preventive maintenance. Mine is close to 20 years old and at a little below $60 (that is with shipping) and with RockAuto I think somewhere around $132.00 before shipping; it only makes sense. I can not check it for leaks every day and if it it is the first leak and I start it with the right conditions it can blow the intake off. I read where a man'* daughter had an old Buick and it happened to her one morning, BAM; and Dad finds the intake in pieces; it is the dual spark thingy.

Anyway, back to the problem. I drove it this past Sunday to a couple of places; tank reading around 1/4 of a tank, without any problems. I stop to make a left turn into a fuel station; stop and wait for several cars to past, engine idling smooth. Go to give it the gas to pull on into the station and it hesitated, did not cut off, then went. Since I was sitting still, I would think it would not be a fuel slosh problem and I did not notice it acting as if it wanted to cut off when I did a slow stop from 45; no hard braking.

Any ideas?

I am wondering if the fuel level gage is very accurate; it is a '93. When I do a fuel pressure check, it is with the regulator vacuum tube connected; so of course if the regulator is working the fuel pressure is going to be reading steady. Do you/should you do a fuel pressure check with the vacuum tube off the regulator? Don't want to damage anything.

I realize you stated it sometimes does not happen when the tank is low, but has it ever happened when the tank is full.

Don't let high pressure fool you. You can have high pressure, but not enough volume.

In the past, the cut off happened either on stopping; which was more rare, or on making turns; which at times was very frequent. However, I saw it cut off with 1/2 tank. I rarely have a full tank; I always seem to be driving on nickels and dimes.

The only reason I did not go ahead and switch the fuel pump out before; other than they are expensive, is that I am going to have to do the job alone. Which means I probably need to build a cradle for the tank I can attach to the jack so I don't have to worry about the tank falling and tearing the fuel lines or power wires.

Or is it possible to loosen the straps where the tank lowers enough to disconnect everything? The only tank related job was Mum'* '83 LeSabre; replaced a leaking rusty tank and I had help; plus, different lines and mechanical fuel pump at engine.

Yes, that is true; the pick-up sock could be clogged. I put cleaner stuff in the tank every so often because I have read this ethanol junk they are forcing us to run can cause gum deposits in fuel pumps and injectors.

Look at this site, you might be able to find some ethanol free gas in your area.
pure-gas.org : ethanol-free gas stations