300te PCV system?
 

1989 300te
I changed my wife's PCV system on her Volvo 850...a whole bunch of parts, all clogged with thick oil deposits. Before: oil soaked engine, poor fuel milage. Now, 200 miles later, no oil leaks, no use of oil...beautifully clean engine.
Do we have anything like this on our 124's? I never see it discussed. I have poor fuel milage and my front seal is leaking. Wondering if the seal is just a 'symptom' of too much pressure in the engine (as was the Volvo)?

The PCV system on the M103 couldn't be simpler. The big hose on top of the air filter housing connects to the valve cover. There's a chamber inside the valve cover that acts as an oil separator. The orifice(s) in this chamber can become clogged, but it's rare on a well maintained engine. If this does happen though, you'll see oil collecting where the hose attaches to the filter housing. If it looks clean, leave it alone. If it's a mess, you'll need to remove the valve cover to unclog the separator.

Your 850 should have a flame trap that does need to be cleaned or replaced. It's a plastic insert that has an array of small holes and they become blocked.