Cobra Intake and PCV sucking oil issues.

5.0Droptop

...all those nights we shared, and you're a dude??
Special Agent Mukity-Muck Whats in Charge Round Here
May 15, 2002
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I had this ocasional problem with my stock intake but now that I installed the cobra intake its become more noticeable.

The problem: Some times when I shift into second and hammer it then leave it in second and back off the gas it will puff oil smoke out the pipes briefly. I belive its coming from the PCV valve sucking oil up and then burning it. It dosent do it all time so I know its not rings and the heads are fairly new etc. The cam I have pulls reall good vacume. I had tested it before at idle and it pulled 17.
So under hard accell and letting off Im sure its creating strong vaccume.

I know this is a common problem with mustangs but what alternatives are there to fix it? Can you connect the PCV hose somewhere else?
A filter? Something.

Its embarassing to have a nice car and show off then have oil smoke puff LOL. Makes it look like a POS heh.

Any Suggestions?
 
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Is it a true Cobra lower or is it an explorer lower? When you installed it did you see a small metal baffle riveted under the PCV valve hole?

From what I've seen and read you can plug the PCV hole in the lower intake and put breathers on the valve covers. If you have stock or stock like valve covers, the screw on type that replaces the oil cap should be good enough.
 
Thanks for the reply. Its a FMS Cobra intake both upper and lower.
It has the baffle below the pcv valve and it has a Screen also.

Its oil smoke cause I smelled it.
 
I wonder if you could put a push in filter where the PCV vavle is? If you could find one to fit the grommet.
 
Vaccume is vaccume. You have small lines for the fpr,egr,and the vac tree. The rest get hooked up as needed. I am certian that its correct.

This is a common problem with 5.0 efi stangs. Anyone who has pulled an upper intake and saw oil in the lower can attest to it.
 
I have the same problem with mine, except I am not using much oil, nor am I making smoke. I have a breather cap on the valve cover where the oil fill was. I still get some oil sucked through the pcv. It pisses me off, I wonder if plugging it with my breather cap still on will hinder performance due to crank case pressure?
Ted
 
stupid stupid mustangs, no real fix it looks like. i guess we are going to loose oil no matter what, oh well if you make a canister atleast it wont be all over your intake (especially my freshly painted gt40 gurrr.) This whole subject has me feeling helpless =( im still going to try that adjustable valve :shrug: :bang:
but hey, i never knew i had the problem until now, so its one more thing for me to worry about! :lol: :nonono: :banana:
 
Thanks. I have some of those oil air filters at work somewhere, Im gonna look around and see what we have for a do it your self project,
 
Fox Saleen 163 said:
Is it a true Cobra lower or is it an explorer lower? When you installed it did you see a small metal baffle riveted under the PCV valve hole?...........

Just curious...why did you specifically ask about the explorer intake??? Do you know something about it related to burning oil??? Thanks.
 
I just did a "cheapy" fix suggested by the guys on cornercarvers, as i figured they might have some issues bigger than ours??...I had the same oil mist in my intake tubes...
The SN95s have a 6" straight shot pc to the intake...I changed that over to a 12" pc....It now comes "straight" up 8" and then loops down to the intake...Thought being, the oil mist will be suspended in the 8" upright and fall back versus being sucked to the intake....another add on would be an old school PCV valve in that return section to the intake...
My intakes coming off here real soon, so i can see if it really helped???
 
I added catch-cans in between the pcv valve and intake, and in between the valve cover breather nipple and the throttle body. They do a pretty good job of catching not only excess oil, but condensate as well.

5.0Droptop - how many miles on your car? What kind of shape are your valve guides/seals in? Without knowing any more than what's contained in this post, I think it's more likely your smoke during deceleration is being caused by something other than a pcv source. I don't think that there's enough oil kicked around in the lifter valley and then pulled into the intake to cause that level of smoke. As valve guides are worn, one of the symptoms is smoke upon start up, and during deceleration.

There is no significant difference between the Explorer and Cobra lowers. They are essentially identical - biggest difference is the lack of a threaded boss for the ACT sensor in the #5 runner. The pcv set up (in the lower) is identical to the stock HO manifold.
 
Michael Yount said:
5.0Droptop - how many miles on your car? What kind of shape are your valve guides/seals in? Without knowing any more than what's contained in this post, I think it's more likely your smoke during deceleration is being caused by something other than a pcv source. I don't think that there's enough oil kicked around in the lifter valley and then pulled into the intake to cause that level of smoke. As valve guides are worn, one of the symptoms is smoke upon start up, and during deceleration.


My heads are completely redone and like new. I just put them on last year and probably have less than 3k on them.
This dosent happen very often but when it does it will briefly puff a oil smoke cloud and then go away. It only happenes when I run the rpms up high and back out of it fast like in second gear (No smoke at start up).... It did this ocasionally with the stock intake but seems to do it more often with the cobra. :shrug: