Misfire in cold, then oil leak (w/ pics)

[Buzzcut]

So about a month ago we had some bruttaly cold days. Two days in a row, on my commute home, I had serious misfires for about a minute, to the point that the car had trouble moving (but did not stall). After about a minute, the misfires stopped, and I drove home the rest of the way without incident.

Shortly thereafter, I noticed a small oil leak coming from the front of the stiffener plate. I removed the plate and took some pics.

I didn't have any noticable oil consumption when I checked the oil shortly after the misfire, so I'm not entirely sure if the leak and the misfire are related to the oil separator issue.

When you get the oil separator leak, where do you see the leak under the car? This leak is on the front side of the oil pan, I guess sort of under the oil separator.

[TwinTurboGTR]

That sounds like the OSV. If the valve was frozen, air blow-by couldn't occur, blowing the valve out. That sounds about right where the oil is coming from.

[JCL]

Agree that it sounds like the oil separator valve. The trouble with guessing exactly where the oil could come from is that when the valve freezes shut and pressurizes the crankcase, it can leak anywhere, such as the valve cover, or from the valve itself. The valve is a likely cause, but you just need to follow the leak up to the highest point to make sure it hasn't also caused a leak elsewhere.

[jpnut]

Originally Posted by JCL

Agree that it sounds like the oil separator valve. The trouble with guessing exactly where the oil could come from is that when the valve freezes shut and pressurizes the crankcase, it can leak anywhere, such as the valve cover, or from the valve itself. The valve is a likely cause, but you just need to follow the leak up to the highest point to make sure it hasn't also caused a leak elsewhere.

Second that. I had this repair one year ago. I still have to clean the residual oil underneath. Best of luck.

[Turbo_Bimmer]

A trick that someone told me to find oil leaks (and I tried it succesfully), is to wash the suspected area with engine degreaser, wait until it dries completely, then spray baby powder all over the suspected area.
Go drive the truck and inspect. You should see brown spots on a white background where it leaks. Easy to find. Then rinse the powder with water before opening the engine.

[TwinTurboGTR]

That or slip a clean piece of cardboard back there. And spray will end up on the cardboard and you can simply take it out, whip out your 10mm and 12mm socket and start tearin er down!