Oil in air intake?
 

Hello I just purchased a 96 2.3 ranger with 140k on it.. it has oil in the air intake.. it looks and smells like engine oil so i'm assuming that's exactly what it is. From what the guy was telling me it was sitting.. so I'm guessing a valve was sticky and oil shot up through the valve cover vent.. but I really have no idea. Does anybody have a clue?

Re: Oil in air intake?
 

Does it have a K&N air filter

It seems like a stock cone. Although my 93 ranger had a box. There's a house that runs between the air intake and the top of the valve cover. So I think oil is coming through that breather. doesn't seem like a ton of oil but it's present. Enough to drip from the intake when taken off.

Re: Oil in air intake?
 

Sometimes when people apply too much cleaning oil to the air filter (like the K&N ones that are periodically cleaned), this can suck the oily substance up into the intake tube from what I remember.

Re: Oil in air intake?
 

yeah that can happen and what that usually does is get all over the maf sensor and make your engine run poor. i'm just confused why i'm getting the brown engine oil in my intake lol runs fine as far as i know.. i'll probably learn more when i put it on the road.

Re: Oil in air intake?
 

what happened was the when the guy put oil in he forgot to put cap on, this happened when i was young with my kia rio, it destroyed air intake , master air flow censor burnt up and tore up spark plugs

Re: Oil in air intake?
 

so you're saying that the only way oil is getting into the intake is if the cap was left off while running?

Re: Oil in air intake?
 

Not the only way. Does your motor have a PCV valve? Or a crankcase breather valve? In my old Cherokee which didn't need one, I had a similar problem. My old shop teacher told me to put one inline. Once I put it inline, the oil in my air filter stopped.

Re: Oil in air intake?
 

During high vacuum situations like idle and steady lower speeds, the flow through the PCV system is from the air intake, through the closure tube, through the crankcase, then into the intake manifold and on to the cylinders for burning.

At low vacuum and high cylinder pressure (WOT acceleration, for example), the increased crankcase pressure also forces part of the PCV flow backwards through the closure tube into the air intake. How much flow goes in that direction is related to blowby and that is caused by leakage past the piston rings.

Finding a small amount of oil and/or tarlike deposits in the air intake is normal. If there is an excessive accumulation, then it is probably caused by one of 2 things:

• A severe oil overfill in the crankcase (possible);
• Blowby due to worn piston rings (likely).

Re: Oil in air intake?
 

it looks like there's too much oil in it judging by the dipstick. i'm going to have to drain it before i can confirm. thanks for the info.. i'll update when i get a chance.