Altima SE 2.4L

• Automatic transmission
• 102,300 miles

This actually started last year on my dad's car. Car just conked out on him whenever he drove locally. Mechanic said it was the distributor and we had it changed and it did it again. Back to the shop for tinkering and we took it back and conked again. Back again and then nothing. For a little over a year. Then in April on the way home from my sister's house the car died while idling on a major highway. TWenty minutes later it finally started up and got it home however took it in to a new mechanic and he said it was the distributor again however the distributor shouldn't conk out in 13 months. My old mechanic took the car back and replaced it with a new distributor(still a rebuilt one not a new one)and my father conked out at the ophthalmologist's office. Car comes back and we conk out at the shopping supermarket. AFter two weeks in the shop, they now tell me it is the computer and a new one costs $1,000. No way--car isn't worth it. So I find one at a salvage yard for $175 and finally two weeks later after shipping and stuff we get the car back and it conks out five minutes later. I will say that the gas tank also only had three gallons left in it as the car gas meter read E. Not sure that has anything to do with it--both times though???? The first time I threw in high test with dry gas and not sure that did it so I filled up the car with gas yesterday and threw in dry gas and will test it to see if it works.
Any suggestions, anybody???

Update from May 5, 2009: More information that may help. When the car conked out back in April of this year, I took it to a different mechanic closer to where I was at the time. He the Engine MIF or MIL light was on and he checked everything out and said it was somethng called the cam sensor which I had just had replaced 13 months ago--which doesn't make sense. Now the first time this happened in 2008 and we had the distributor put in, we also started to throw in high test gas here and there and just got back into the routine of using regular when prices of gas went sky high. So, now I'm wondering if this whole thing could be as simple as the octane of the gas we are using? Any body have suggestions. Help!!!!