1997 Ford F250 XLT super cab short bed
4 X 4
460 ci EFI
5 speed manual
K & N air filter since new cleaned & re oiled 2 to 3 times anually
Stock dual air intake tubes from airbox to throttle body have a plastic connecting piece about half way - this piece was molded with a diameter reduction necking it down about 50 % - the reduction taper was removed opening it up to full diameter within the first year.
230,000 mi
only Name brand Premium fuel since new
oil consumption since new about 1/2 quart : 1500 miles
fuel consumption 14 to 16 mpg since new
Only quality brand named components since new ( Autolite plugs etc. )
original owner - new motorcraft oil filter & Castrol Syntec 10w30 every 3,000 mi simce new in Nov 98
90 % highway miles wife and i only drivers - never abused
Fuel filter changes 2 to 3 times anually. All other fluids changed anually ( trans, transfer, diff’s )

Live in very remote area - competent diagnostic wrenches hard to find - especially when out of the box problem.


Problem started about a year ago - oil in air box

Imediatly checked PCV - ball free - cleaned anyway - found T fitting broken - lower portion of T on PCV - rearward part of T to intake manifold by firewall - forward part of T to evaporative system - ordered new T and replaced - Did not fix problem

Vacuum line to manifold is solid metal line with tight slip fit vacuum hose connection @ manifold. disconnecting @ PCV and holding finger over line end - strong vacuum at idle - remove finger - idle increase

Engine runs as new - starts with touch of key hot or cold - idles with no visible shake - No engine noise - no smoke - instant throttle response - no change in fuel consumption - slight increase in oil usage due to blow by - last oil change noticed gasket leak on oil pan - prob. pressure related - Wife noticed a fluctuation ( hunting ) in oil gauge while driving a couple of days ago - she told me when she got home - fluctuation only happened for brief time then stabilized - oil about 3/4 quart low - possibly very slight smell of gas in oil - viscosity not noticably different nor was finger rub - no mech eng noise or smoke

have not done compresion check - but I really don’t see any indication that rings are likey suspect - maybe i just don’t want to see that

Just found your site - awesome - read all 63 ford pages -did find one thing in your Q & A - "oil Fouled Air Cleaner " answer - I don’t wrench for a living, but no GM, Ford, Or Mopar that I’ve ever run into flowed into the engine through the PCV - they all flow out of the engine through the PCV - OOPS

Great site and appreciate all of your effort and help

Thanks

joe