Here is the short story. Recently I noticed a good amount of white smoke coming out of the tailpipe after letting off the throttle after running the car hard. No smoke under throttle, just in vacum when I lift. I was thinking all sorts of bad thoughts. So today I go and check my catch can and notice that it has a several ounces of fluid in it. I took out the drain plug out of the bottom and it was mostly oily water that came out. A good amount of it though. I guess a lot of this is from condensation in the lines and the aluminum can itself. Now the can is filled with brass brillo type pads to catch the oil. It is plumbed from the vent in the valve cover and back to the intake. I take the car out again and run it hard and guess what? No smoke. I am going to add another catch can for the EGR, but this is a little strange Anyone else notice this happen before?

 

i dont have any experience with this...but i do agree with you ... it could be vapor..i have seen vapor condense in the lines before...never in the can itself..

 

Never saw that with mine yet, but it seems to just be some sort of condensation buildup. Just to be sure id check your head gasket

 

Never had any watery fluid in my catch can, always oil, so I can't be sure what to tell you, but maybe a headgasket??

 

+1 on condensation, but this is very strange. Completely empty out the can and check it everyday.

 

H2O a byproduct of combustion in an internal combustion engine? Can't be!!

This is normal on that side of the engine and you'll get more if you're running meth.

 

If your catch can has an aluminum breather or aluminum lines to it it will get condensation from hot to cold transitions. Like if you boil water and cover it on the stove when you lift the top you will have steam and water (condesation) on the lid. same concept.In order for it to smoke when you let off the catch can must have been more then half full as when you let off you go into your highest point of vacum causing this oily watery residue to be sucked upward and a slight bit back into the the combustion chamber causing it to smoke when you let off.

 

The can itself is made of billet aluminum and I can see water condensing in there from the hot cold transitions. I have not emptied it since I installed it about 6 months ago. There are no other signs of a headgasket problem and the coolant is full plus I would certainly see smoke under acceleration if I had a head gasket probelm. The can however was no where near 1/2 full I would say about 1/4 full. The vacum must have been sucking the water up through the brillo pads that are probably soaked with oil and dumping that back into the intake. I hope the vacum is not going both ways and sucking water back into my valve cover I am going to put a check valve in that line just in case and a fuel filter on the line that is going back to the intake. I am also going to add a second catch can for the EGR valve. The crankcase pressure that I experience is high enough to easily blow the dip stick tube out at anything over 24 PSI. Let me tell you it was very disconcerting to see all this smoke coming out of my tailpipe after just having built this engine myself. Very relieved that it was somehow related to the catch can. Now I just have to fix my newest problem. Suddenly my defi oil pressure gauge is stuck at 100PSI! I guess it is time for a new sender.

 

sounds like a plan oil pumps working awesome lol