I got a 1997 Ford f-150 4x4 extended cab flareside with a 4.6 triton with about 158k on the motor.

My truck uses about 1 Quart of oil every 2 weeks and it has no leakes under the vehicle but yesterday I noticed when I took off from the light kinda quick a puff of white smoke shot out and then there was nothing.The truck runs good other wise except for the lean bank 1 and lean bank 2 codes I dont know if this would cause the smoke or not.Was wondering if anyone had any ideas on a easy fix or the problem instead of me having to replace or rebuild the motor.I have tried Lucas oil additives and fuel additives and it only seems to help a little but only for a few weeks.Any help would be appreciated.Thanks

 

Also does anyone have a diagram of the vacuum lines on the 4.6.trying to pinpoint which vacuum is causing my lean codes.Thanks

 

on the 5.4 the questionable vacuum lines are on the drivers side, close to the exhaust manifold.. the hotter places on the motor probably heat the rubber, gets hard and cracks... it does not hurt to pull off each hose one at a time and check it for "hard" and cracks. normally these are the small 3/16 for 1/4 inch ID lines.

 

I know you'd hate to, but pull your plugs and check them for carbon. That could tell you if oil is getting into your combustion chamber. Or, you could pull the oil cap off while its running and feel for vacuum or if its blowing smoke out. If its blowing at all, you have blow by and your cylinders/rings are worn out.

You might also want to change your pcv valve. It may be broken and on many motors that will cause some oil consumption.

 

Thanks for the comments guys.I think I will end up doing a tune up on it and change the PCV valve which either has been done since buying the truck over two years ago so it is probably do for those anyways.Still would like to find a diagram or something on the Vacuum lines for this truck so I can know where some are hiding and some are not.Thanks again.

 

Had a similar problem with my 99 5.4, with oil use and that puff of white smoke when moving off, turned out to be valve seals in my case