Problems with Subaru Legacy Ex22

Good friends I have a problem with a subaru legacy ej22 which suddenly the engine loses reling and gives the impression that will remain in 3 or less cylinders working but already check spark, check injectors and nothing, the check Engine does not turn on, I do not know what to do if they could help me I would appreciate them beforehand beforehand

Hello everyone, Gamm_84, I have read its post several times, with Derepente, it refers to the problem is intermittent. If so, when it occurs more, in cold, in the heating stage or already hot ..., the other the fault occurs a certain time or once it occurs is permanently unstable? Excuse me for so many questions, but it is essential more info to help you. Finally when he expresses that I verify spark and injection, was it with the engine failing? Any extra data is used for the effects of the diagnosis. Greetings.