oil in the coolant
I'm not a Porsche expert, but oil in your coolant is never a good thing no matter what year/make/model you own. Take it into your favorite mechanic and have it checked out immediately.
Check your oil cooler seals, this is a common failure on Porsche 944's. The oil cooler should be external, usually the coolant leaks into the cooler or the oil leaks into the coolant. If you continue to attempt to run the car like this you will eventually get a "milkshake" in your pistons and be in a world of trouble. My $0.02 -Jordan
You have a leaky headgasket that is sipping oil into the cooloing system, replace it as soon as you can...
At first I would say headgasket as well but can you determine if it motor oil or trans oil I believe that model has trans oil cooler in the radiator and that cooler may be leaking trans oil into the radiator otherwise its a head gasket stop driving immediatly other wise coolant is in the oil as well and will cause you to spin a bearing then you screwed
Ahhh... The dreaded "milkshake". I'd first replace the oil cooler seals. Most common source of this problem on these cars and should be done as part of normal maintenance considering the age of your car. Headgasket is also a possibility but oil cooler seals are most likely. http://www.clarks-garage.com/shop-manual/lube-01.htm
Replace the following parts: 1pc. 944 107 147 03 1pc. 944 107 153 02 2pc. 999 707 043 40 1pc. 999 707 145 40 1pc. 999 707 146 40 1pc. N 043 815 3 These are the gaskets and O-rings that need to be replaced between the oil/water heat exchanger, it is located in the housing that the oilfilter is mounted on. Just remove and replace. Porsche has a special tool to center the housing correctly over the openings in the engineblock. Without this tool: make sure the plunger for the oilpressure will move freely in it's bore. If this gets stuck/does not move freely the engine may suffer from low oil pressure or it will blow it's filter off of the engine. If you bought the car recently: make sure the seals haven't been replaced recently, as you may have oilcontamination in the coollant for a long time, it is not easy to flush all the oilresidu out.
Intermix (oil in coolant or coolant in oil- thick coffee like substance) can be caused by several problems, depending on your model too: -cracked cylinder head -blown gasket -oil cooler cracked/broken -cracked cylinder in the engine If you have any questions, call my mechanic, he knows everything about these cars: www.mbmotorsportsrepair.com. He will be able to help you with all your q's. They did my engine rebuild, I highly recommend them.
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