Oil in the air intake hose

[Npeterson212]

My 08 Aveo5 LS was running horrible yesterday and the SES light was on. At one point the light started blinking and the car began to stall out. After I pulled over and checked the code, it was the camshaft position sensor. I just replaced that sensor and while tearing it down for the replacement, I found a mouse nest in the bottom of my air box which caused some serious buildup in there. I also notice that there is some oil in the air intake hose and there is a hose that runs from the top of the crankcase over to that air intake hose that it seems to be coming from. Aside from cleaning out the air box and dropping in a new filter (and launching an all out Bill Murray style attack on the mouse) is there anything more I should do or any reason to be concerned about the oil making its way into the air intake hose? It certainly doesn't seem normal, but then again, I don't know what the purpose of the hose is that allows the oil to make its way there either. I'm a weekend warrior that knows just enough to get myself in trouble and then force myself to figure out how to get out of said trouble!

Thanks!

Nick

Edited with pictures attached.

[Npeterson212]

Apparently the pictures attached sideways from the iPhone. Sorry!

[Stumpy]

When I did my short ram intake set up, I noticed that there was a waxy, grease like oil below the return hose. I would say it is normal because I, too, have experienced this build up.
A note of shameless self promotion- check out the intake swap thread I posted for some nice HP gain.

[Npeterson212]

Thanks for the info. I just pulled the plugs to swap them out and there is a ton of oil on the two middle plugs. I'm going to re-do the gasket and see where that gets me. That's a great write up on the intake. Might be in my future!

[Stumpy]

Proceed with caution though-
my wife's old Cavalier had a similar plug issue but it turned out just to be improperly torqued or sealed and it didn't allow the fuel to compress/ burn all the way. Changing the plugs and see where it takes you, it may just sort out. Which gasket are you talking about anyways?

[Npeterson212]

Proceed with caution though-
my wife's old Cavalier had a similar plug issue but it turned out just to be improperly torqued or sealed and it didn't allow the fuel to compress/ burn all the way. Changing the plugs and see where it takes you, it may just sort out. Which gasket are you talking about anyways?

The valve cover gasket. I changed it about 50,000 miles ago with a leak. I am just about to turn 100,000 miles.

[Stumpy]

That seems like a short run on a gasket. Did you use a paper / cork or the nice felpro silicone?

[Npeterson212]

It's a rubber gasket-more like a big O-ring that sits in a groove around the outside of the top of the valve cover. That's about the only thing I can think of that would cause 2 of the 4 plugs to be coated with oil like that. I may be wrong though. Last time, I had oil comin out of the corner of the valve cover and when I took the cover off, part of the gasket was melted to the metal that it sealed against. I just pulled it off there and it looks like it may have been compressed around the two inside plugs too much. I used all of the torque specs when I put it on there but it obviously didn't hold up. The new one is on and the cover is back on it. We will see what happens from here. here is a picture (from the Internet) of the blue gasket I replaced. Seems to be a common issue!

[avguy]

..... I just pulled it off there and it looks like it may have been compressed around the two inside plugs too much. I used all of the torque specs when I put it on there but it obviously didn't hold up. ...

Did you install the first gasket in a criss-cross tightening pattern of the bolts, and also 3 stages of tightening (or at least 2)? If you just tighten each bolt to the spec torque all at once, and go around the clock, that would likely be the cause of the pinching and early failure that you experienced. I've done the gasket on both of our Aveos using the procedure I described above, and neither have leaked a drop over the multiple years they've been in place, so I can say for certain that these gaskets can, and should hold up well.

[Npeterson212]

I did use the cross tightening method for it last time. I'll do it again and see how it holds up! It probably doesn't help that I drive it like I stole it. It's kind of an extra car for our family and I truly do beat it when I drive it. 80mph highway - quick shifts....its held up well considering.