Hello,

I have a 1998 Ford f-150 STX. It has the 4.6 Triton approaching 200,000. I have noticed recently that when I leave it setting at idle for a few minutes and then rev it up a little it will shoot out a poof of blueish white smoke. It does not smoke at start up or when you get on it just after it has been setting for a few minutes at idle. I have had people tell me that it is possibly heads loading up what do you guys think? Thanks in advance.

 

blue smoke is oil blowby. what are the heads loading up with? you more than likely have valve seals going bad and it happens off idle because your oil pressure is higher but eventually the seals will get bad enough it'll do it on start up and then all the time.