Oil in Coolant Reservoir Uncover the Warning Signs

3G TL Problems & Fixes - Oil in coolant reservoir and radiator - This is for my uncle's TL-S. It's a 2007 Automatic. Replace oil cooler. Fill cooling system w/ fresh water. Add a small(!) amount of detergent to coolant tank, run vehicle for a short bit. Drain. If oil is leaking into your coolant, the coolant will be overflowing because oil is adding to the coolant. Therfore, your oil should be consumed. The tech said he thinks it's the DSG transmission cooler since the oil in the coolant is very dark, vs the engine oil which is as clean as a whistle. I was on a trip, over 300 miles from home, when my 2014 Passat TDI started spewing black engine oil out of the coolant overflow tube. This is quite a common problem with the 272/273 motors. Replacing the seal alone will not fix the entire problem you have at this point. You ... It's your oil cooler. I promise. Drain and change NOW before you build too much sludge throughout cooling system and heater core. It's going to ... The most common sign of oil in cooling system is the presence of a slimy milky-brown layer in the coolant. Oil in coolant is a leaking oil cooler. Coolant in the oil can be many many things, with the head gasket being low on the list. Coolant in the cylinder is a ... Blown head gasket\cracked head if you're not getting a CEL with a miss. Oil and coolant only combine into that nice brown goo under high ...