1995 Toyota Corolla Sudden no start

Two weeks ago I left for work in my Corolla, stopped off at plant number 1 for a pre-op, came out 15 minutes later to drive to plant number 2- 45 miles away and my car would not start. Engin cranks but would not fire. I had it towed to the dealer where they informed me my computer has gone bad. I wnet to the local salvage yard and purchased a unit for $100, better than the $1300 dealer was going to charge for a re-built unit. Dealer installed the new computer and car is running, I picked it up drove it home, parked it in the garage. A couple of hours later I started it, backed it out into the driveway, shut it off, 10 minuted later I tried to start it, engine would crank but would not fire. Dealer did a full diagnostic of all componets - any ideas? I sent original computer to California to be rebuilt.