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Im getting a misfire code for each cyl, but the idle is good around 700 warm, the only problem i have is in fourth or fifth gear it wont go past 4k rpms, it accels fine but say in fifth if i go past 83 the engine acts as though a govenor kicks in and kills the engine until its under 80. Does same in 4th not sure what speed but around 4k rpms. I dont punch the throttle but i commute on the highway daily and usually cruise about 80. I put new plugs in and checked the coil packs and they were fine, air filter is clear, so maybe injectors?