My 850 took a turn for the worse today, I tried to add in an oil catch and flush the coolant. Immediately I'm getting white smoke, and it's from the turbo and exhaust.

Just pouring out the exhaust, fizzing out the turbo.

Pull the dipstick and it pops, there's tons of pressure in the crankcase, but i just changed the whole PCV system <5000 miles ago. Little milky crap on the dipstick. No more than a few ounces of coolant low. I undid the connection to the catch can and little smoke coming from there. Left it undone to relieve pressure. After an hour I managed to get the smoke down to a "not noticeable until people pass me" to drive home...

First thing my hood flies up and luckily did not smash my windshield or cause an accident.
I'm driving and the idle starts dipping below 900, 600, 400, 250. I'm trying to balance the throttle and brake to stop and let the car die. The car itself is shuttering, and stuttering while idling and accelerating.

Get home, it's idling at like 200-250 so i kill it. There's oil sprayed all from under the cap and dipstick.

Smoke is getting less and less, but engine is running worse and worse. If there's water/coolant in my engine, would an oil change and some seafoam be able to rid the water before it does damage?

I understand this is most probably Head gasket
Is it possible this is a bend rod, or blow piston or something else.

 

I would get the compression check on that car ASAP. Also, I would get rid of the catch can. It sounds like it is not installed correctly or something. Was the car ok before you installed it?

 

I had some what low numbers across the board 140's last time i tested it dry, wet they all came up. I'm going to empty out the pan first thing tomorrow and change back to the synthetic mix. Then pull the plugs and crank it over a few times. See what numbers i get, I'm sure if I'm forced to order HG it'll be from you guys, like $150 for the whole HG job.

I might pull the turbo and see it's just full of crap from the engine too.
The catch can seems unrelated. Unless my Tstat went from being stuck open to closed. We'll see

 

Not good running coolant in the motor, via from bad head gasket. The big thing would be letting the car over heat. Just don't do that.

How did the hood fly up? I did that once in my 960. Was sitting with the hood up a little and then drove off without closing it. Bent the hood and my hinges. Scary!

 

After 4 hours of driving around a parking lot, popping open then closing it and fiddling in the dark i forgot to push it down. the middle latch is gone because i didnt get around to making a custom release cable for the grille. Yea hood hinges and fenders are all chewed up.

The car was putting out rich fumes, and been suspicious of the HG for weeks now.

On to the good news, after changing out the oil there's improvement. I only got one and half quart out though. If i leave the dipstick pulled up just a bit, it relieves enough pressure from the engine so that the billows of smoke do not pour out the exhaust, but as soon as i push it back in the pressure builds and out smoke comes from the exhaust. worn rings

Maybe tomorrow, drain oil and fill again if its not 30* with 30 mph winds. Most difficult conditions to change oil. I'll check the plugs and pressure test too

Otherwise car runs fine with steam from dipstick and oil squirting out there at times.

 

how is the PTC valve is it clean? if it is plugged could definitely contribute to your issue

 

^^^^

This is true too. The numbers will tell all as soon as you get the compression checked.