Engine Oil in Intake, normal?

doctorj357

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Curious what everyone's thoughts on oil getting in the intake with the older (E6SE) lower intake design. Were the older lower intakes (86-93) subject to allowing more oil being sucked into the PCV than say (94/95) cars? I know they made improvements to the oil splash shield over the variations.

I recently did a top end rebuild on my 95 GTS. Went back to stock. I even bought a correct 94/95 upper intake, and came with a oem lower. I just presumed the lower was matching. It wasn't until after I installed everything I realized the lower was the older (E6SE) design (RF-E6SE-9K461-D3A). Problem is, I don't remember if mine had the splash shield or not. I know its supposed to, but I just can't remember if it was there. I know I took a picture of it once, but of course can't find it now and I don't want to take the intake off just to look underneath.

I'm trying to figure out why I am getting a decent amount of oil sucked through the pcv, more than before the rebuild. Before it was a Edelbrock upper/lower, which had a minimal splash shield, just like the oem E6SE has. Now, how do I know I'm getting oil? Before the rebuild, I installed a oil catch can and observed a very slight amount every month or so. After rebuild, seems like an ounce every 100 miles. Plus each time I take the upper intake off I can see traces of oil going down the runners. Its not dripping, but its there.

The pcv is brand new with maybe 2k miles on it. It was on there when I had the Edelbrock setup. But I also had a e303 cam then and was definitely making less vacuum at idle. Now, same pcv setup, but have a oem replacement cam, making the expected draw at the intake. I have Fox valve covers and the oil fill neck has the line running to the air intake. That was like that before and after the rebuild but no signs of oil going through that. I thought about the potential 'worn ring' scenario but the car is low miles (57k) so I would doubt it, but can't rule anything out.

It's not affecting the car's driveability or anything. It seems to run & idle just fine, but does smell a little. I'm sure that's the smell of oil burning up as its being sucked in. Just curious some thoughts on what might be typical causes.
 
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90sickfox

Wasn't a pretty sight...and I've got big hands
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Is the screen filter below the PCV valve ?
 

08GT500

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Hi,
Agree with above, pull the PCV Grommet & snap a pic.
PCV is the correct oe part?
Running the EGR?
No smoke at cold idle, or any other time, oil odor only, the odor is exiting the pipes?
Best!
John
 

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doctorj357

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I am running the EGR with no issues. IAlso no smoke at any idle (cold/hot), just oil odor

The screen is there. It was brand new when I put the lower intake in. The rubber grommet was brand new, Dorman I think, it didn't fit in there snugly, so I used a little permatex black rtv. The pcv fits in there, but I wouldn't call it snug
02MKvUK.jpg



The PCV is a Motorcraft (EV-98). This was brand new in the box in the parts included with the car. I don't think they even make this anymore, the replacement is EV-98B. But I tested the valve and appears to work, not stuck open, air only flow one-way
82Wol12.jpg
 

doctorj357

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Does the vacuum source matter for some of the components? I've seen a couple different configurations how the PCV, FPR, EGR are connected. Crude drawing, but here is how mine is currently setup


iWK5ywv.png
 
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General karthief

wonder how much it would cost to ship you a pair
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Curious, why the deviation from stock.
Example:
why a catch can on a n/a engine
Why vacuum from the neck and not the intake body for the fpr and egr
 

doctorj357

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When I got the car, it already had the edelbrock intake on, and that's how the vac lines were routed. (doesn't mean it's correct but it seemed functional).

The catch can came with the car, in a box of parts, unused. I figured it couldn't hurt to install it. It wasn't to remedy anything really

So this spring, when I did a rebuild, I went to a stock intake. I just put the vac lines back the way I found them initially.

I'm getting the overwhelming feeling it's not setup correct? The stock intake I bought, didn't have that little vac tree that threads underneath the intake. I thought that was for 79-93 cars because of how the egr was setup differently than 94-95.
 

General karthief

wonder how much it would cost to ship you a pair
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I moved this to the 94-5 tech threads, I missed that this is a 94-5 car.
Are you using the 94-5 intake?
The vacuum lines look like they work but I'm not a expert.
I would compare your routing and make it mimic stock locations as much as possible, the factory does things for a reason, like fpr by itself, don't know the reason though.
In reality, if it works why fix it? Except this thread started with an oil in the intake problem, the routing as it stands may be the problem? :shrug:
 
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doctorj357

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Well that's the thing, I have the correct 94/95 upper intake, but I apparently have an older Fox (E6SE) lower. So wasn't sure what forum it belonged. In my initial post, the concern was over the differences between the oil splash shields. Best to my knowledge, mine doesn't have one unlike the correct 94/95 lower that should be there

Everything on the car works, and well. Just can't understand why the oil is coming through. Doesn't appear to be affecting it other than some odor, and increased draining of the catch can
 

General karthief

wonder how much it would cost to ship you a pair
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Aug 25, 2016
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If it is showing evidence in the catch can check the screen below the pcv to see if it is soaked in oil. You may have to pull the lower intake to check the baffle. I don't know of any difference between the 86-95 lower cept maybe that baffle.
 

revhead347

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If it's of any consequence to you, I have an oil seperator in line just like you have, with the vac lines the same way. New PCV valve, screen multiple times, and I still get oil in my intake. I get oil that builds up in the throttle body even. If you ever figure it out, let me know.

Kurt
 

doctorj357

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If it is showing evidence in the catch can check the screen below the pcv to see if it is soaked in oil. You may have to pull the lower intake to check the baffle. I don't know of any difference between the 86-95 lower cept maybe that baffle.

Yeah that's what I was thinking. I'm trying to avoid pulling it because I just got it all back together a few months ago. Yesterday I pulled the plugs and they look fine. I might just hold off a make it a winter project.
 

doctorj357

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If it's of any consequence to you, I have an oil seperator in line just like you have, with the vac lines the same way. New PCV valve, screen multiple times, and I still get oil in my intake. I get oil that builds up in the throttle body even. If you ever figure it out, let me know.

Kurt

Interesting. I haven't seen any evidence in the throttle body so far. Not sure what that's about. But if that oil splash shield is missing 'i suspect', I'm pretty confident that will cause it. Problem is can't remember what it looked like before I put it on.

It's yours the stock 94/95 lower intake?
 

revhead347

Apparently my ex-husband made that mistake.
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Interesting. I haven't seen any evidence in the throttle body so far. Not sure what that's about. But if that oil splash shield is missing 'i suspect', I'm pretty confident that will cause it. Problem is can't remember what it looked like before I put it on.

It's yours the stock 94/95 lower intake?

No, it's an aftermarket intake. The weird thing is that it has a seperate breather filter, so it isn't sucking it up from the valve cover either.

Kurt
 

08GT500

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I have cleaned out the baked on crud/sludge from 5.0 uppers over the years through the TB flange deep down to the 90 degree turn, where the oil gets baked on, takes a night of solvent poured in & brushing to remove it. Very clingy goo.
Take a peek inside the Edelbrock one it ran, if it’s there- the same issue was, if not, aside from a leaky intake gasket, it’s the lower for certain. Pull it, Repair/replace & be done with it, or itl never go away.
You came this far-right? What’s a few hrs & maybe a busted knucke or two.
Cost: intake gaskets:20$, Correct used lower:50$, 2 Bandaids, 50c, Job well done: Priceless.
I’d suggest a leak down test, compression test to check your engine’s internal health, just so you know with it’s uncertain history.
Then, once you’re sure Vacuum lines are routed as OE, if it’s still pulling oil...
Once Oil’s actually within the Baffle & pooled up
in the shield, vacuum keeps sipping away at it & sending A shop Vac with a 3/8” hose sealed airtight to the end will pull a good amount of the accumulated Oil out.

A band-aid AKA; TemporaryI fix I came up with It does work.
Run a hose with the same ID as the OD of the PCV’s base, same OD as the Grommet that plugs into the lower. Clamp it to the large base of the PCV, which now sits about 6”-8” above the lower, insert the base of the same larger ID tube tightly into the Grommet hole in the lower(can add an aluminum ring inside the hose, so it stays in tight).
Why did something so silly even work?
We traded vacuum strength for surface area
The larger ID tube will cause a Vacuum level drop & will no longer be strong enough to pull/hold the oil droplets in suspension, much less up pull them into the line, through the PCV & into the intake, Venting continues.
(Patent Pending)lol.
They make an adjustable regulator PCV valve that splits idle & high rpm vacuum into 2 separate adjustments to meet the evac needs of the motor Only...90$:oops:
In a high mileage (or hard driven) motor, or If heavily modified, where there’s increased blow-by I’ll run covers with a hole in each, shields with baffles inside a PCV into the cover closest to the front of the motor, a sealed non-vented with a nipple, both tubes routed to the intake.
Sometimes you can locate stuff pretty easy on SN via posting a Wanted ad., possibly already for sale.
Can’t beat the Guarantee, Members will not be so kind to one that sells junk parts.
 
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