Why is oil going into the throttle?

[240Stilo]

I took off my intake one day and saw that there was oil that has been coming down from the hose connected to the valve cover. What I did next was take of the black tube off the throttle and saw the bottom was covered with oil. I then came to the conclusion that this is the reason why the whole intake side of my engine bay is drenched with oil. This sometimes leaks onto the alternator which sucks because it then starts to smoke. Is oil supposed to be coming down from the valve cover hose and if it is should it ever be so much that it soaks my car with oil?

[DuffMan]

Blowby?

[DSC]

SOME oil is normal. It's routed into the intake to get burned away. But the amount your talking about sound like something is wrong. I don't know what it would be tho...

[240Stilo]

What would happen if you just sealed up the fitting that sticks out the valve cover?

[DuffMan]

You shouldn't seal it up but you could put a breather on it, but that's only a bandaid. A leakdown test is what you really need.

[240Stilo]

Leak down test as in using the dyes in the oil to find the leak?

[240Stilo]

Originally posted by DSC
SOME oil is normal. It's routed into the intake to get burned away. But the amount your talking about sound like something is wrong. I don't know what it would be tho...

Why does some oil actually have to go in there?

[AceInHole]

Some oil doesn't HAVE to go in there.... i.e. in setups where breather filters are used.

Another option:
Pull the valve cover. It should look like this:


If that plate has somehow loosened I could see a way for more than the usual amount of oil to get to the breather fitting.... otherwise it really shouldn't.

[240Stilo]

Are you talking about the plate that is across the whole inside of the valve cover? because my valve cover sure doesn't have that. And I was thinking of adding a breather filter but I was afraid it would only get covered with oil. And what does your pic mean where it says that your valve cover isn't sealed in the back?

[AceInHole]

Originally posted by 240Stilo
Are you talking about the plate that is across the whole inside of the valve cover? because my valve cover sure doesn't have that. And I was thinking of adding a breather filter but I was afraid it would only get covered with oil. And what does your pic mean where it says that your valve cover isn't sealed in the back?

That whole plate is sealed except for an opening in the back where indicated. The breather filter goes into the sealed area between that plate and the top of the valve cover. The opening in the back where it isn't sealed is the only place oil or air can flow through, thus making the path from the breather fitting much longer and more complicated, and assumably harder for oil to get all the way through.
This is an S13 valve cover. I won't be able to check my S14 valve cover untill tomorrow, but I'm fairly sure it has the same thing on it. If your valve cover doesn't have that plate, that could definitely be a reason so much oil gets into the breather.

[240Stilo]

S13 valve cover as in KA24DE or KA24E?

[anotherblusi]

Hmm can't you just get an oil catch can.... isn't that what a catch can is for?

[240Stilo]

Isn't that just a brand name can with a hose? or does it do more than just be a can?

[thx247]

oil catch can is literally a can which catches oil that comes out your vaccum line a the top. It catches the oil so that it does not go into your engine. Cars with FMIC's run them to keep their IC's from gathering a whole bunch of oil. Its a worth while 40 dollar investment.

[AceInHole]

Originally posted by 240Stilo
S13 valve cover as in KA24DE or KA24E?

DOHC

[240racer]

Originally posted by 240Stilo
Isn't that just a brand name can with a hose? or does it do more than just be a can?

it's just a can with a brand name on it, but it's pretty, so get one. If you make your own, make sure it can handle the chemicals and temperatures that it will see. I've seen those polycarbonate nalgene bottles used with good success in quite a few race cars. I don't have one yet, so I just drip on the ground for now. I have also seen the nalgene bottles replace the coolant overflow tank when you need to move it for custom turbo type setups.

[the head]

im just speculating but could it be that the check valve on the back of the valve cover is stuck open allowing more oil to be sucked down

i could be way off but just a thought

[240Stilo]

AceInHole pretty much got it covered. If his valve cover has that plate that blocks oil to the breather fitting then that's probably why i'm getting so much oil in there.

[misnomer]

Yes, pay attention to Stilo and Ace. If you don't have that plate there, then you've found your problem. It would probably be easier to source a new valve cover than just that plate, but do it. That plate is there to keep an excess amount of oil from entering the motor. Hell, I've never even been able to feel oil on my throttle plate or anywhere else in the throttle body.

[kandyflip445]

It's a problem with the Positive Crankcase Ventilation(PCV) system. Check the PCV system for clogged hoses/valves. This could cause the oil in your air cleaner. Along with what the others have posted and wear in your cylinders. I've included a image of a generic PCV system.

[AceInHole]

OK, I checked my S14 valve cover today. Looks like this:

Definitely has that plate. It's definitely sealed with the those slit openings. You missing that = bad. End of story.

On a side note: I don't need my S14 valve cover anymore (was just going to use it as a decorative piece at my apt). If you wanna buy it e-mail me an offer at [email protected] . It's painted black but it's scratched to hell from the turbo install (oil line kept scratching the paint off as I kept taking the turbo on and off).

[240Stilo]

Well AceInHole settled my problem but thanks to everyone else too.