This would be a hassle, but I would suggest removing the tank and taking out the fuel sending unit/fuel pump assembly and checking it closely for anything amiss. It looks like from the pics in my Haynes manual, and the exploding view posted earlier in this string, that the pump is connected to metal tubes running from the pickup screen, correct?
I would inspect all of the very closely, especially the parts closer to the pump, since the problem seems to occur when the tank is less than 1/2 full.
My guess would be that there is a crack in the metal tubes, or the connections to the pump inlet are bad, or something along that line, so that when the tank gets below 1/2, and you're turning left or whatever, the pump sucks air.
The centrifugal force of turns could cause the assembly to shift and thus open up a break somewhere, and the pump sucks air.
Once you get the assembly out of the tank, grasp it by the top and down by the pickup screen, and see if there is movement in it, and if you can see where something is broken, or loose, where air could get in the metal pickup tubes.

I was helping a friend with his Volvo once, and the thing wouldn't start when the tank got below 1/2. You could hear the intank pump run, and the other pump ran (It had 2 fuel pumps), but no gas.
We removed the intank assembly, and between the pump and the pickup, there was a 4 inch length of rubber hose, and the hose had a tear in it, so when the gas got below the tear, the pump sucked air and car no runny.
Simple repair.

I have a feeling that your situation will be something similar.

My 93 doesnt do that and I do over 20 around left turn on ramps

I have a 92 SSE that was losing power on turns, I recently replaced the fuel pump and filters and it fixed it.

Everytime the tank got below 1/2 a tank of gas, any sharp turns or sudden braking would cause sudden loss of power. Sometimes the car would even stall on braking hard. It did idle ok though and ran fine as long as I had more than 1/2 a tank of gas.

The new fuel pump fixed it, bad news was that it isnt easy to change, its in the fuel tank. I didnt go with a cheap one, but got the OEM pump, hopefully it will last longer.

Andrew
92 SSE
97 SSEi

In 93, I had the probem in right turns.

Factory (not sure if a TSB or not) for missing baffles in the tank. It was fixed under warranty. No reoccurance.

Also a resister was put in the wiring harness to correct the guage which would go to empty on a fill up of the gas tank.

Hal,

I like your other rides! A '65 tri-power goat and a '67 goat! You must have Pontiac in your blood!

Welcome to the forum.

well i dont know about anyone else....but i was recieving this problem as well with a really looped out gas gauge...i dropped my gas tank and found there was broken baffels on the inside which casued the gauge to show 1/4 tank but it was really empty i got a new tank put it back in and everything seems to be grea the gas gauge is working the best it ever has and i can take any corner on fumes now without stalling out or loosing engine power. I posted this just so others can read...i tested my fuel pump while i was doing all this and found it was fine for what factory was so i decided to keep it unlike the other guy(crazy driver?!?!?!?! i forget). Anyway this is jsut incase you have this prob and its NOT the fuel pump or hte oil sloshing or feul sloshing all to 1 side.

Gosh this just happened to me this morning! I have a 94 though.. I put a post in the 92-99 forums!

later

Same thing happens to my with my 92 ssei. well at least i am not alone, only usually happens when i am 1/4 tank or less. really sucks.

I have this same problem with my 92 ssei as well only it happens no matter which way the car turns only more so on left turns, i have also recently had the gas tank off the car to fix a couple leaks, on the passenger side the tank is longer but skinnier(leaves for the same amount of gas on either side) this problem only happens when the car is less than 1/2 tank. easiest way around it was to never let the car go below half.

I have a '93 and never had this problem.