1996 F-250. Be idling fine then check engine light pops on and is just like loosing 4 cylinders instantly. It stays running, rough though, and then after a few minutes will clear out and run fine. It does this on and off at different times. Today after letting set for 7 hours, fired up like nothing was wrong and drove for 15 miles, shut it off, started it up and was sputtering within 4 seconds. Left it idle and it cleared out after about 4 back and forth sputter sessions.