I have a 1999 Impreza 1.6 wagon. I am having a problem where the vehicle will run for short periods and then shut down. If you try to restart immediately it will not restart however if you put it down for a while and try restarting it after some hours it restarts and runs for a short while before shutting down again. Initially the run period would be for a day or two. Now its is for very short periods, sometimes less than an hour. The vehicle is a standard street version with no modifications at all. I recently replaced a knock sensor. I have had it on the diagnostic machine but no issues show-up. Has anyone experienced this problem and what are the possible solutions..
