Cars

Most likely on that car you have a cracked head they crack in the number 4 cam journal and suck oil into the coolant jacket. You would have to remove the cam to double check it but those engine's are known for doing it.I have replaced a lot of head's on those engines for cracking.I have seen all the way up to 2002 saturn s model single cam head's crack and leak oil into coolant. You would remove the cam and pressurize the cooling system and see if the cam journal is cracked. You have to take it apart anyways to find out why the oil is mixing with the coolant. So your sure it's oil in the coolant?Also is the there any coolant in the oil?