Oil in my Upper intake Plenum - Normal or Bad?
#1
Oil in my Upper intake Plenum - Normal or Bad?
Due to an abnormal idle issue that has been traced down to low compression in #2 cylinder left me looking for answers so I pulled the upper intake manifold and the valve covers and I didnt see anything loose, broken or unusual. So I am thinking its a bad valve for sure. However my brother an I noticed that the upper intake manifold was very oily! Also the heads were very gunked up with oil(slug). We pickled the motor using diesel fuel and got some of it out, and then added fresh oil and a can of seafoam. However here is what my intake looks like after cleaning it up and driving around town (20miles or so). TB opening-
Upper Plenum Chamber-
Lower Plenum Chamber-
Another Upper chamber pic-
Also to add my truck is not blowing smoke or using oil. As well as my plugs look like new considering they have about 1000miles on them.
Upper Plenum Chamber-
Lower Plenum Chamber-
Another Upper chamber pic-
Also to add my truck is not blowing smoke or using oil. As well as my plugs look like new considering they have about 1000miles on them.
#2
I had the same problem. I traced mine to the PCV valve. There is a way to re-route the vacuum line for this, but I haven't done it. But if it's still rather oily, I have heard of capping the nipple on the back of the Upper plenum and routing the PCV rubber line down the passenger side fender well and installing a breather filter element, exactly similar to the one installed it the filter housing on the driver side air box. That way it prevents trash from entering the cylinder head with normal driving.
#7
I rerouted my pcv to the vacuum tree on the center of the upper intake and plug the other hole with a vacuum cap from the help section at autozone. The reason people say to do this is because it dumps all the blowby on the back pistons and that makes them run hotter, so the rings/pistons wears out. Here are a couple links. There are a couple ways to do it.
http://fordfuelinjection.com/files/Reroute_PVC.pdf
https://www.ford-trucks.com/forums/1...questions.html
Here one where a person had a problem with the reroute. I had a extra port on the vacuum tree, so I had no problems.
https://www.ford-trucks.com/forums/1...e-warning.html
http://fordfuelinjection.com/files/Reroute_PVC.pdf
https://www.ford-trucks.com/forums/1...questions.html
Here one where a person had a problem with the reroute. I had a extra port on the vacuum tree, so I had no problems.
https://www.ford-trucks.com/forums/1...e-warning.html
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#8
It's normal. I don't mind as long as it isn't excessive amounts being pulled through the intake. By your pictures it doesn't look like you need to worry, Look at it as a way to lubricate the top end of the motor and catch all the little dust partials that got past the air filter . That isn't enough oil to cause fouled plugs so I would just leave it alone.
#9
I rerouted mine since the compression for #8 was so low as compared to the others. Read where it sucks all the blowby into the cylider from the back of the plenum. I did what Raptor posted. Worked out well.
If you don't have another vac on the "T", just replace the vac line from the Brake booster to the back of the plenum and route the other line from the PCV to the "T" on the Plenum.
Note: Didn't intend to be repetitous Raptor. Good job on the links. I looked and looked and finally found this when I had problems several months ago. Had never heard of this problem till I saw 120 lbs comp. in cylinder #8 compared to 145 and 150 in cylinders #5, 6, and 7.
If you don't have another vac on the "T", just replace the vac line from the Brake booster to the back of the plenum and route the other line from the PCV to the "T" on the Plenum.
Note: Didn't intend to be repetitous Raptor. Good job on the links. I looked and looked and finally found this when I had problems several months ago. Had never heard of this problem till I saw 120 lbs comp. in cylinder #8 compared to 145 and 150 in cylinders #5, 6, and 7.
#10
Well here is how my PCV is routed, not to mention I'm not really sure how that much oil is getting in my intake like that, because my PCV looks really clean. The only thing I can think of is that the little rubber hose that connect to my Oil filler neck to my air duct tubing is sucking in oil! But my TB's are oil free!
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