Tale of Woe with a PCV Question, Eventually
 

I have an '01 S60 T5, 152,000 miles. I was driving it on the freeway and the little orange light came on and a text message that disappeared faster than I could read it. It did not come back on. After about 30 miles I started to climb our local mountains, about a 5000' climb in 34 miles. Car was fine, though I did notice that the cruise control would not hold speed.


At or near the top, very briefly, I got the orange light again, then the 'low oil pressure - stop right away message' then it went off again. It came and went, not in a pattern I associate with low oil pressure. (i.e., wasn't coming on at idle, then off when revved.) My thinking was a bad oil pressure sender, since I'd had precisely that problem with my wife's escape the weekend before. I had plenty of oil, I'd checked it that morning. I parked in front of our local auto parts store and asked about the sender, which they naturally did not have in stock. I started driving the 4 more miles to our cabin and the car didn' sound quite right, so I turned around and drove 1/2 mile back to the auto parts store and parked it.


Checking the oil level (finally...) nothing on the dip stick and a puddle under the car. Bought two quarts and added them. Nothing on the dip stick. Long story short, engine down over 5 quarts. Filled it up and drove 4 miles, losing 2 quarts in the process. To my surprise, the car sounded fine during the next 4 miles.


As far as I know the PCV system has never been serviced. On disassembly, the front intake camshaft seal had come out and was just loose behind the pulley. So I did timing belt, water pump, idler, tensioner, and all three cam seals. (There is, from the factory, no cam seal on the intake rear position.) I didn't do the crank seal since it was clearly not leaking.


And I bought the PCV kit and took the manifold off and replaced hoses and the oil tank. Now my assumption was that the crankcase had pressurized and popped the seal out. But nothing discovered in my work appeared to be blocked. The passage back into the oil sump from the bottom of the tank was maybe 30% blocked. The passages to the tank about the same. I didn't find anything completely blocked at all. I cracked the tank itself open and it did not appear to be blocked though it had some build up. If these had been arteries I'd have said watch your diet, see you in a year.


I put it all back together gave it 6.2 quarts of Mobil 1 and it sounds and runs great. So here's my question:


1. If I now do the 'glove test' on the dipstick tube or the oil fill hole, the engine does not suck the air out of the glove. It certainly doesn't inflate it with pressure either, it is just pretty much neutral. Does this mean I still have a problem and there should be strong draw on the glove when I do this? The glove certainly doesn't blow up like a party balloon as some people have illustrated on UTube. If the lack of suction means something is still not right with the PCV system, any ideas on where to check? I did verify that all check valves I came across in my repair were working. I did find some minor vacuum leaks here and there in all this disassembly.


I asked my Volvo mechanic and he said seals can pop out like this when they get hard and shrink a bit without there being crankcase pressurization. So maybe my assumption that a clogged PCV system had caused the seal to pop out in the first place was not correct.


Thanks.

Did you have your tech measure the oil pressure after the new PCV? You may have something caught up in the oil pick up as well - my tale of woe is I had a similar intermittent oil light on my '12 VW CC - crank case was full - so they dropped the pan and it turned out to be junk in the oil pick up. (48K miles! got a new engine under warranty)

I think the low oil pressure warning resulted from the car working its way down from 6.2 quarts to 1 quart. The pressure would drop then the oil pump would get enough to raise it briefly. When I added the 5 quarts the light went out and has stayed out. I just drove the car from Riverside to downtown LA and got 32 mpg and it is running great. I've been in cars that scored main bearings when down a couple courts so it amazes me that I could lose that much and still have an engine.


My question is pretty simple, and all that background was to avoid a lot of obvious suggestions that had already been dealt with. It comes down to whether an early S60 with a PCV system in good repair truly needs to pull vacuum through the dipstick when tested -- or whether simply not pressurizing is enough.