I test drove a Crew Cab 4x4 5.4 today. They claimed it had sit for about a week but when they started it there was a moment of white/blue smoke from the exhaust. I owned a 99 5.4 and never had this problem with 150k miles. This 5.4 only has clost to 80k on it.

Any ideas on what may cause this or is it common on the newer 5.4's and nothing to be worried about.

THanks,

Rod

 

The first time I started my van on the new car lot, it blew out a puff of smoke. Modular engines seem to have a tendency, if they are started and run for only a short time (such as being moved around the lot at a dealership) to blow out a puff of smoke on a restart. If they are fully warmed before a shutdown, there is no smoke.

I am not guaranteeing that this is the case with the truck you're looking at, but it is a common occurrence with modular motors. If you are able to drive the truck until it's fully warm, park it, and restart the next day with no smoke, I'd say things look pretty good.

George

 

sounds about normal actually

every Ford I have ever owned did that. from my 1984 F-150 with 302 to my 2006 FX4 with 5.4. The key seems to be sitting for prolong periods. My experience has been that they do it when sitting for 3+ days without running

my Mustang and Expy are so new that the seals are too tight still...but I fully expect them to do it as well.

your main concern should be the oil consumption. My motors ate maybe 1/2 a quart between oil changes which is very normal.



if that truck is sitting low on oil, then i'd be concerned. also, how does the tailpipe look/feel?

 

I checked the exhaust pipe and it was actually clean with no residue at all. It was a clean truck but it just didn't give me that warm cozy feeling.

Rod

 

Every modular Ford we've owned has done that. Just randomly, you go out and start it and it will smoke for just a second.....

 

My 04 has never done it....nor did my 92 w/302.

 

My '08 has done it a couple of times and I have less than 30K on it. Worried me a little bit but hasn't done it a while. Seemed to do it more when I was parked on a crazy angle? Very weird.

 

Although I used to think it was random, it is really not.

If started cold and run for just a couple minutes (like moving it around the yard to make way for another car), and then parked overnight or longer, it will smoke every time. It is noticeably worse during cold weather (I'm in Michigan).

After a full warmup and drive, it won't do it. I'm guessing that the mod motors at dealers will be very likely to be started briefly and shut down, to move a truck into a different row or something.

My van now has 73k miles and I just went 6500 miles on a full syn oil change without having to add a drop of oil. And my first experience with it, when it was brand new, was starting it up at the dealer and having it make a little cloud of smoke.

George

 

Well I thank the valve guides are leaking by. After a vehicle set say overnight and it is started and you see light blue smoke it is almost always the rubber on the valve guides getting just a little stiff.Allowing oil to seep by and at start up you get smoke.

 

My truck a 2004 F250 w/ 5.4 does the same thing when it is started and moved a short distance and shut off. When the truck is run for any length of time no smoke is visible. My truck does not burn any oil between oil changes,and I use mobil 1 syn 5w20 w/ 5000 mile changes. With the modular engines smoke at start up is normal when the engine is started and shut off in a short time, 1 min or less.

 

I've got 107k on my 04, and I never get a puff of blue on startup, after sitting or whenever. I do seem to use about 1 quart in 5k miles though, but have NEVER seen any blue smoke from my 5.4L