1989 Pontiac 6000 spark plugs

Engine problem
1989 Pontiac 6000 V8 Wheel Drive Type unknown Automatic 110000 miles

This has happen to me twice. I let my car get near empty and put the highest grade gas(93) in it. The first time it acted like it ran out of gas or the battery went dead. The next day my brother went to look at it and got it crank but it ran bad until I ran all that gas out that I bought. This was the first time. The second time I also let in get near empty and put 93 grade in again. I drove about a half of a mile and was at home. But when I went the next day to crank it it would not start. So my brother came again to start it but he could not start it this time. He spot check it like the battery and fuel. Then he checked the spark plugs he found out that they had no fire to them. He has replaced the computer and something esle but still want start. Could you please help me. It is the only car I have Thank you, shar3nn@yahoo. Com