I have a 2001 ford f150 5.4L. It has 76k miles. every now and then it puts out a big puff of blue smoke, then stops. Any idea what could be the problem?
Under what conditions? Start-up? When you give it gas? When you get off the gas? At idle? On shutdown? How much oil are you using? How is your maintenance? Regular oil changes? Blue smoke is usually oil getting past the rings or leaking down overnight with valve stem seals getting brittle, and then into the exhaust somehow . . . and it will cause problems with your CAT. Rocketman
it was just at morning start up, but recently about 1 mi after starting she blew a cloud for about 100 ft. It hasent been doing it in the morn since a recent oil change. As for maint. I have had the truck since 33000 and change the oil every 3 to 4K. she has seen very limited heavy service, mostly just drive her to work.