I have an 04' F-150 FX4 5.4 with 36000 on it.My brother-in-law noticed the other day when i started it that it let out some blue smoke when first started but then cleared up! it did it two more times that day then just stopped!and i havent noticed it since!I talked to my dealership and they think that maybe an injector was sticking?any body have this problem or ideas? thanks

 

Doesn't blue smoke usually indicate oil and white indicate fuel??

 

I think an injector sticking would cause more of a blackish smoke (fuel related) rather than blue smoke (oil related). Just my opinion, but it seems there may be something more going on, especially with a truck with that few miles.

Robbie

 

Mine did that once..........
But it was after I released the key to quick and it didnt start. Something happend and I had to wind it a bit for it to crank. When it did start, Blue looking smoke. Has not happened since.

Keep an eye on it. If it happens more, surely take it in.

 

Since it only happens when starting, that usually indicates oil running into the cylinder via a valve stem seal, not sealing correctly. Why not try a good injector and top end combustion chamber cleaner see if that helps. You may have some carbon buildup on the valve stems.

 

You took the words out of my mouth. I had this problem on my 2002 F150 4.6L. It started doing it somewhere around 20K miles, but only once in a while after it would sit for a few days before I would start it. It was also intermittent So duplicating it to the dealer was impossible for me. Although injector cleaner never helped mine any. I think the only true fix would be to re cut the valve seats. I didn't worry much about it an drove it until I had 56K when I traded it in on my current truck. I did notice a little oil loss between changes but not more than a quart at the most.

 

For what its worth on another forum for Mustangs I read that the new mustangs will do this after sitting for a while. I believe the consensus was (theirs not mine) that this was normal and caused no damage.

 

Right, it isn't really going to heart anything. But it doent make it right. The 4.6l seem to have the problem the most.

 

I agree but if it is just occasional I don't see any real problem. A bad valve guide would cause excessive smoke after any type of idle time (especially on). The 4.6's seem to do this when they are high mileage but still run fine.

 

Thanks everyone!I talked to the dealer and they recomended i try the injector cleaner to.thanks for the help.

 

Smoke on start up can also be caused by condensation build up in the tailpipe and muffler, it is basically burning the water and producing vapor

 

My 04 FX4 5.4 has done this every once in awhile. I haven't noticed any oil consuption between changes....

 

Yes Its Injectors Its A None Problem Get It Fix Soon Or U Run The Chance Of Hydro Lock And A Bent Rod

 

my 94 with a 302 does this alot also. the smoke is related to my deployments. under normal driving, the truck will never blow any smoke at all. every time I get deployed though, the truck will sit for 2 to 3 months before it gets started back up and it'll blow white/blue/black smoke for the first day or so when started up. it does not however use a drop of oil. always 5 qts in, 5 qts out

I just attribute it to valve leakage and combustion chamber fouling from sitting an extended period of time. I'd think you're safe with you truck. how long does it site before you notice the smoke?

 

it sat about a week and a half,but it hasnt done it since.