My father has a 99F-150 4.6L XLT. It has about 25,000 miles on it. Ford replaced a head gasket at 19,000. It has now started to blow blue smoke out of the tailpipe when it is started after it has sat overnight. Anyone have any info on what could cause this? I plan on bringing it to the dealer, but just wanted to get a heads-up before I go. Thanks

 

Probably valve seals. Not unusual and not a real problem. Have an old Chev. Van with only 65 K miles that does the same thing for the last 6 years but I have never had to add oil between changes. Don't expect much help from dealer.

 

Welcome to my world!!

I posted on this in the past, and have the same problem. Ford cannot duplicate; the smoke happens very infrequently (every 2 weeks +/-). My 2001 4.6 has 22,000 miles.

I currently have a letter to the Ford regional rep; I'll update if successful.

I've talked to some mechanic friends, who believe it's a valve seal; probably only one. When the engine happens to stop in just the right position, oil seeps into the combustion chamber. I wonder why my dealership couldn't figure this out? Hmmmm......

Good luck, and let me know the luck with your dealer.

 

harting, don,t worry about it....its just a little oil from the valve gear finding its way into the cylinders overnight. The residual oil in the cylinders migrates south overnight too, so a little help from above on a cold start is actually a good thing. Next time you are driving down a steep hill, let the engine do the braking with your foot off the gas, if the valve seals are going, there will be a puff of blue when you get back on the throttle.