camero headache

This 95 camero came in with what seemed to be a rotor that had blown apart. I replaced the distributer,cap,rotor,wires and plugs. All AC DELCO parts. It ran great for about 20 minutes then just stopped running.I scanned the computer and the only code I got was18 and after following the trouble shooter I ended up replacing the computer. It also blew the rotor off again. After putting in the computer and a new cap and rotor it runs good in the stall but when you try to drive it, it cannot handle any load. There are no codes and I pulled the distributor back out and it is still good. I put it all back together and it just spits and sputters when you try and drive it. I would appreciate any information you might have. Sincerely,