Oil in Throttle Body

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K

Kmart

10 Year
Joined
Jan 22, 2012
Threads
9
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64
Location
Richmond, VA
Guys,

I replaced my valve cover gasket a couple of weeks ago, and completed a few other PM items while I was at it. Since then, I have had some rough idle issues and decided to replace the air intake tube to make sure that wasn't the issue. When I took the old air intake tube off, I found some motor oil pooled on the bottom of the throttle body. I replaced the pcv and hose while I was doing the gasket and also replaced the other hose on the top of the valve cover (I think it is some sort of breather that leads to the throttle body). Can someone please let me know how to fix this? I am guessing this has something to do with my idle issue, but I have no idea what is causing it, or how to fix it. Thanks in advance, guys.
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Not sure the cause, but a fix (or bandaid) is an inline oil seperator to catch the oil before it goes into the throttle body. I use one, never had oil going into my throttle body that I knew of, at least it never caused an issue. Every oil change the catch can is 3/4ths full though, so some oil definitely was getting by and going to the throttle body.
 
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Google search PCV catch can and it will give you plenty of options. I went with a CNC'd aluminum one for the bling! :grinpimp: You add the catch can between the PCV filter on the valve cover and where it enters the throttle body. I have mine mounted on my battery tray. I'll post a picture.
 
When I had my valve cover off for powder coating I was surprised to find the inside of the baffle was full of sludge. It might be worth a try to flush out the oil baffle (?? via the PCV and breather holes if you don't want to take it off again). If the baffle is plugged with sludge the bottom of the PCV valve could be sitting in a pool of oil.
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Kernal said:
When I had my valve cover off for powder coating I was surprised to find the inside of the baffle was full of sludge. It might be worth a try to flush out the oil baffle (?? via the PCV and breather holes if you don't want to take it off again). If the baffle is plugged with sludge the bottom of the PCV valve could be sitting in a pool of oil.
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Excellent point, that PCV valve shouldn't be sucking oil at all. The baffle is designed to prevent that if I recall.
 
Not the baffle/PCV expert but AFAIK they all suck some oil. Just thinking that if the oil mist that does get sucked up into the baffle can't drain out quick enough more than the usual amount might get pulled into the PCV??
 
Thanks for all of the great replies. I am definitely going to add a catch can to the PCV line. I am still a little baffled by what I have going on. I did my first real "distance" trip in my 80 today - about 220 miles of high speed highway driving - and I had my oil level low light come on twice. The first time was about 80 miles into the trip. I stopped and added 1 quart of oil before continuing on the trip. I got the oil low light again after about 80 more miles and added another quart of oil. I don't see any signs of external oil leaks in the engine bay or under the vehicle, and I don't think the engine is consuming the oil (no oil smoke in the exhaust). I can only guess that the oil is being sucked out through the PCV valve. Clearly, I should not be losing this much oil. Does anyone have any idea what could be causing the engine to lose this much oil. It is getting expensive to keep adding quarts of Mobil 1 every 80 miles!

I am wondering if the baffle in the valve cover is leaking or something? I don't know if this is supposed to be sealed, but I did clean quite a bit of rubber from around the rivets and edges of the baffle when I removed the valve cover. I did not have my valve cover professionally cleaned by the way.

Thanks again guys.
 
AFAIK the purpose of the baffle is to trap the oil mist/spray from the moving parts (camshafts, timing chain, gears, sprockets,etc) and then allow the condensed oil to drip back down into the engine but some of that mist gets sucked up by the PCV valve. I had the same question when I had my valve cover off, how important was the sealant around the edges of the baffle pan, IDK, but I don't think removing some of that sealant would make any major difference in how the PCV system worked as the baffle pan is already open on top and bottom.

Are you sure the oil level was full-up before you started the trip, checked the level with a warm engine?? Any visible leaks? What do you see if you look straight down into the PCV hole (PCV removed)?
 
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Thanks, Kernal. I am guessing that the oil level was low before I started the trip, but honestly, I hadn't checked it in a while. I guess I am more concerned about the fact that I put a quart in during the trip, and it seems to have gone through that quart in approximately 80 miles.

There are no visible leaks, so I guess I should pull out the PCV valve and have a look inside. The PCV valve and gasket are new - is the valve easier to remove when new? I had a tough time getting the old one out, but the gasket was old and hard.
 
That's it? Not other responses to this persons posts? I have same issue. I'm thinking of "de-sludging" somehow, then seafoam a couple times. Then I'll do compression check after I drive it a while to see if it's still using oil like it was.

Other posts and sites say could be sludge, bad/sticking valve or bad piston rings. So, I figure de-sludge and sea foam a couple times to see if that changes anything (as in I drive 440 miles and see if I still have to add oil and how much).

If nothing from desludge and sea foam then I'll do the compression check and possibly vacuum check.

Anyone have a recomendation on which compression "checker" to buy for the 1fzfe?
 
New cars also have some oil entering the intake thru the pcv system. IMO just clean it up with some throttle body cleaner and then move on with life.
 
Wanted to bump this to see if anything was discovered.

I too have excessive oil usage (In the neighborhood of 1 quart / 150 miles). It seems to have become worse. Took throttle body off last night and found oil in the throttle body before the butterfly valve. So it has to be coming up through the air ventilation hose? I imagined some slipped through the pcv but there is a healthy amount in the throttle body.

Cleaned the egr passage way of some serious carbon residue. I was thinking of taking off the valve cover to inspect underneath, but prior to that I have been searching on here for a couple of hours trying to find the cause. BTW the motor runs great. Recently have replaced front main seal, oil pump cover, valve cover and dizzy o-ring. Got rid of most of my oil leaks (still have some on the pan gasket) but the oil consumption seems to be getting worse.

Will probably take the valve cover off to look at the baffle, I've been thinking of trying Royal Purple to see if it might help the rings to reseat them. I've had guys swear by the stuff saying it helps reseat rings. I was wondering if that's what I've got going on here. I have not run a compression check.

Would love to see if anyone has any answers.
 
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