A few days ago I was carting some people/gear around in my 93 960, we were pulling a lot of grades with a headwind, so the car was running between 3500 and 4500 rpms for several extended amounts of time. The other day I noticed it was leaking a bit of oil, and there was a fair amount that had blown back and "dotted" parts of the underside. I checked the level, and was 1 qt low. (it has been almost 2k since last oil change) Took the car to the mechanic the other day to have it diagnosed, and I was told that that it was leaking oil from the crankcase ventilation system, that all cylinders had around 125 psi, when they should be at about 170, that there was a minor knock which could be due to a partially collapsed piston, and that the leak I was getting was due to blow-by. I love the car and it runs great. Super smooth idle, revving, and gas mileage. It has 165k on it and I am religious with maintenance. Should I be super worried? try to get rid of it asap? or just accept that it has finally been "broken in" and keep taking care of it......maybe dump a can of "restore 6" in it and see what happens? Any input is appreciated -thanks-

 

Have the Vent box and hoses replaced.
That compression isn't all that bad as long as they are the same all the way across.
One of the vent system hoses could be clogged making it leak oil.

 

Thanks tech, I'll ask my mechanic about it tomorrow

 

I was also wondering, should I be especially concerned about a potential partially collapsed piston?

 

They might mean worn rings.

 

Hoses were all clear, and all the gaskets/seals looked ok, I was just having a lot of blow by. Mechanic said that based on the compression test, the rings were probably worn. It's funny because when I drive the car how I normally drive it (nice and easy) I get hardly any oil leakage, (just a drop or 2 every few days) and whenever I take it on long trips where I am driving at a constant speed for a long time, I have no oil leak out at all. It seems that as long as I don't drive it hard it doesn't leak much at all. Does that make any sense?

 

You might still have a clogged vent system. The more you drive the more pressure builds up in the engine. Then is has to go somewhere.(Leak out as oil)

 

That makes sense.......we'll she's running good and strong right now, and so far I have not lost any noticeable amount of oil. So I guess I'll just see what happens. Gotta wait another month or so for it to warm up enough so I can give the vent system a thorough check.

 

gotta love some of the quirks with these cars......I just did a 400 mile drive earlier this week, and guess what? underside was dry, and I lost no oil. hhhmmmmm

 

+1

 

.....and I averaged 25 mpg, which included various mountain passes with a pair of skis and snowboard on the roof