good one naru
i have an 87 rx with the same problem...it runs just fine and then dies either a couple minutes later or a couple seconds later. what i have heard is the same thing as naru...its the ignitor that sits on the bracket right underneath the coil. with this thing dying like that it wont throw a hard code for the diagnostics to catch. so i would replace the ignitor and go from there. but dont order from subaru because they only (from what i heard) sell a kit, which is the ignitor, the coil, and the bracket. then you just plug it in and go. but subaru wants an arm and a leg for it. my best bet would be going to a parts yard and taking one off of another car. thats what i am in search of right now. good luck