i pulled the throttle body to replace the tps and found oil and black tar substance in the throttle body and intake manifold, where the heck is it coming from and should i clean it up before re-assembly?

 

You should def clean it before putting all back together.

 

i kinda figured that, i am just debating if i should ditch the truck i think it is blow-by and dont know if it is worth me messing with.

 

If you had blow-by frothing from the air cleaner assembly, I would be concerned. Otherwise, it isnt uncommon to have some sludge/gunk in the TB. Unless it's pouring out the TB, it's Ford Tough!

 

I will concur, it is not unusual to have build up in the intake on these trucks. Make sure the PCV system is in good shape, A new Motorcraft PCV valve and a new breather filter are suggested. If it has not already been done move the PCV vacuum line from behind the upper intake to the center vacuum tree.

There was Service Bulletin from Ford many years ago and a production change for re-routing that vacuum supply line.

 

i see some oil in the air cleaner assembly, that little filter is covered and some on the air filter itself but no froth their is a little bit in the oil breather tube that connects to the air box tho. i got a new pcv to install, i didn't see where their is a vacuum line off the tree for it, is there a place to get a diagram of this?and what is the easiest way to replace the pcv? wouldn't blow-by show up as oil on the plugs to?i hope it isnt blow-by but with almost 200000mi it is really possible.

 

As this truck came from the factory in 1993 the vacuum line comes off the back of the upper intake. The bulletin from Ford moves the vacuum line to the center vacuum tree. That is why you probably do not see it.

The best way I have found to replace the PCV is to remove the upper intake. The factory setup uses a rubber elbow hose to attach the PCV to another plastic elbow in the passenger side valve cover. Too many direction changes IMHO. I replaced the rubber grommet in the valve cover then installed the PCV directly into that grommet. From there I re-routed the vacuum hose to an unused spot on the center vacuum tree.

FWIW my '92 F350 w/5.8L engine has over 155k on it. When I purchased it 2 years ago the airbox and filter were soaked in oil. After swapping in a new PCV and the vacuum hose re-route all is dry so far.

 

ok thanks for the help.i will be tackling thus project tom. if i need any more help i will holler.

 

I see alot of our trucks doing this, even when they were almost new.

 

As RLA2005 stated..Here are a couple of pics of my re-route of the PCV.






Overkill, I know, but with pics, it helps even a novice see how it's setup. I decided to go with the copper line as it won't have a tendencey to kink or split or deterioate. 36" and the OEM PCV hose and 3.5" of 3/8s' fuel line hose @ the top of the Vaccum tree. The Copper line i used is for refridgeration and not regular copper line used for sweating home plumbing. It has the same inside diameter of the OEM hose.

 

does this procedure work on the six banger. i have a 92 that blows a lot of oil into the air filter box. i've replced the pvc valve and it does seem to have good vacuum. the hose is comming off the manifold and not the tree. thanks, mark

 

I have never heard of anyone doing this on the 300 I6 engine.

 

i got off work and i started it and 3.5 hours later i got it all apart and the intake gasket broke, so now i have to wait till tomm to put it together. and the pcv was in good working order. thanks for the pix but that is where my brake booster plugs into so where else can i relocate it to? and if i can re-route it do i plug the old vacuume line on the manifold?

 

You can't see where my brake booster vac line is from the pic. It is relocated on the elbow from behind the plenum, where the original PCV valve line was hooked into. I think it takes a 11/16's open end to turn the elbow facing towards the brake booster.

 

how do i hold the intake gasket in place while i put the plenium on with the air cond. lines it is about impossible to go straight down, and i riped the brand new gasket, now i have to drive to town to get another one. i just cant cathc a break any where.