Can't remember how many questions I've asked on this board in the past weeks, guess this is what happens when someone gets a new used car :)
Anyway one of the first things I did after buying the car is to make sure the crank case vented alright. I pulled the flame trap, it was all dirty but not clogged. I replaced it anyway. The small vacuum hose to the intake manifold was totally clogged -- replaced it. The brass nipple on the intake manifold was clogged -- cleaned it out.
It seems impossible to remove the oil separator without removing the intake manifold (if anyone knows a way please let me know). But after searching the old posts, I bought a 5/8 ID hose, pushed it against the oil separator, removed the oil filler cap, and blow into the hose. I could feel air blowing out of the oil filler hole, and it did not took much effort. So I assume the oil separator was not clogged.
Now with a new oil filler cap gasket I tried the jiggle test, and it danced all over the place at idle. But it wouldn't fall. I tried to push it down to 'get it start', still dancing as soon as I let go my hand. If I rev the engine a bit by turning throttle link by hand, it wouldn't stay at all. I removed the oil dipstick and revved the engine, white smoke (or vapor) will rush out from the dipstick hole. No smoke coming out at idle though.
So does that mean the engine has more blow by than it should be? It's only 10 years old and with 100k on the engine, and owned by a lady since new before I bought it. Everything under hood is Volvo, no cheap aftermarket parts and I can see the dealer service from carfax report. So I doubt it has been abused. The oil was still amber color about 200 miles (I know is short...but I guess a lot blow by will turn it black in a matter of 100 miles). No smoke out of tail pipe once the car warms up. The tail pipe is about the cleanest one I've seen on a car with 100K miles -- only the color with metal and rust, not a touch of black soot. And the engine is quite responsive.
Or should it have some positive pressure when revving the engine?
One thing I haven't checked is the bigger hose coming from the the top of the flame trap holder and enter the big air hose right after the AMM sensor. It looked pretty large, is that impossible to clogged? The reason I have not checked is the weird hose clamp screw that holds it onto the big air hose. If that thing needs to be replaced, what name should I mention to the dealer? Thanks.