Excessive moisture in oil

Messages
47
Location
Canada
Thread starter
I noticed that my 2006 G35 has excessive moisture in the oil as the oil cap has a good deal of white condensation underneath. The car is driven short trips but I have not had the problem before. I took the car for a good drive on the highway for 40 minutes but the condensation is back within a week. Coolant is clean and no signs of contamination or coolant loss. The dipstick is clean. What would be causing this excessive condensation to build up?
 
Messages
540
Location
Alaska and Wisconsin
Originally Posted by totegoat
The cold combined with not running engine at temp long enough.
+1. Recently told my oldest to take his sportwagen for a few long drives in Alaska because of his short-tripping moisture under the oil cap. That advice worked. BTW, he runs Mobil-1 Euro 0W-40 as he should. That and the similar Castrol oil is good stuff.
 
Messages
4,112
Location
WA
Originally Posted by mb32
What would be causing this excessive condensation to build up?
If you're confident it's not coolant than it's cool, damp air and/or blow by in conjunction with not driving the car enough to burn off the moisture. In the winter I have a hard time keeping the engine temp high enough to burn off moisture simply due to the cooler ambient temps. Driving around town won't do it.. you need long runs on the highway.
 
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Messages
63
Location
New Hampshire
I run it for 15 minutes with oil cap off to let yellow moisture escape in my 05 cavalier. A little messy but i do not care in this old car....you would have to add some oil afterwards. Leo, NH ....excessive moisture also shrinks filter so change that every 3 k in winter.
 
Messages
1,226
Location
Sask, Canada
Pull the dipstick, if it's not frothy white, your probably fine. My trailblazer always has had the white froth on the oil cap in the winter. 244,000km and 24,000km oil changes and it runs like a top. I change by km driven not time or season. Don't overthink it. Just drive. I you can sleep at night do an oil analysis and get empirical evidence instead of bench racing.
 
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Messages
588
Location
Indiana
I had a Kia that I short tripped continuously in cold weather, it built up condensation like you describe. As long as your not getting coolant in the oil your fine. Only thing that will prevent this is getting the engine up to full operating temp frequently.
 
Messages
47
Location
Canada
Thread starter
I'm wondering if a bad PCV would cause this. I'm driving the same route/conditions as previous winters and never had any condensation under the cap previously.
 
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Messages
10,426
Location
Cincinnati, OH, USA
Engines that have the fill cap elevated up off the oil pan seem to be worse for this issue, almost all Ford gasoline engines (esp.vans) seem to have it in winter. As long as it disappears in warmer weather, my Grand Marquis even had it in warm weather due to a weak thermostat, a new 195F Superstat cleared that right up.
 
Messages
4,112
Location
WA
Originally Posted by mb32
I'm wondering if a bad PCV would cause this. I'm driving the same route/conditions as previous winters and never had any condensation under the cap previously.
Possible. If combustion gasses are backing up it stands to reason that more contaminants, including water, will be found in the oil. Buy a new one and see what happens... also, check your oil cap and dipstick to make sure it's getting a good/tight seal. A bad pcv can sometimes cause a dipstick to pop out creating a point of ingress for contaminants.
 
Messages
47
Location
Canada
Thread starter
Okay I pulled the line to the PCV and it was full of milkshake condensation, and the valve was plugged full. Cleaned it out real well until I could hear the valve rattle. There was good vacuum on the PCV hose so looks like the blockage was only at the end where the valve sits. I did replace the valve covers last year and I am wondering if the aftermarket PCV valve isn't working as intended like the original one. I took the car for a good drive on the highway keeping the revs between 3-4k RPM to burn off any residual condensation in the engine. Will monitor for now, but hopefully the condensation goes away. If not, will re-inspect the PCV and replace with new one.
 
Messages
4,112
Location
WA
Originally Posted by mb32
Okay I pulled the line to the PCV and it was full of milkshake condensation, and the valve was plugged full. Cleaned it out real well until I could hear the valve rattle. There was good vacuum on the PCV hose so looks like the blockage was only at the end where the valve sits. I did replace the valve covers last year and I am wondering if the aftermarket PCV valve isn't working as intended like the original one. I took the car for a good drive on the highway keeping the revs between 3-4k RPM to burn off any residual condensation in the engine. Will monitor for now, but hopefully the condensation goes away. If not, will re-inspect the PCV and replace with new one.
Sounds like a plan.. could be the blockage was also popping your dipstick out and moisture could make it's way in that way too. Did you check your oil cap for a tight seal?
 
Messages
470
Location
Minnesota
I've noticed this recently on our new corolla. I can't stop the short trips so I wipe out the cap occasionally so it doesn't build up.
 
Messages
4,184
Location
Texas
Originally Posted by Traction
PCV valve?
That was / is my first thought . And I agree , the cold and short trips is part of it too . You said , no sign of oil in the coolant . What about coolant in the oil ? Any other sign some thing is not right ?
 
Messages
4,184
Location
Texas
Originally Posted by mb32
Okay I pulled the line to the PCV and it was full of milkshake condensation, and the valve was plugged full. Cleaned it out real well until I could hear the valve rattle. There was good vacuum on the PCV hose so looks like the blockage was only at the end where the valve sits. I did replace the valve covers last year and I am wondering if the aftermarket PCV valve isn't working as intended like the original one. I took the car for a good drive on the highway keeping the revs between 3-4k RPM to burn off any residual condensation in the engine. Will monitor for now, but hopefully the condensation goes away. If not, will re-inspect the PCV and replace with new one.
I would purchase a new / quality PCV valve , anyway & install it .
 
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