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Q: Oil in the coolant tank

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I own a 2003 Jeep Cherokee 2.5 CRD. It started rising in temperature to the halfway mark where it never reached normal conditions, followed by a warning buzz or chime and the oil light coming on and off twice. I then pulled over and switched off the car. I opened the hood and noticed that there was black milky oil in the coolant tank and some smeared on top of the exhaust manifold. When I opened the oil filler cap and noticed some slight milky residue, I then got someone to tow it home. Please help me with some technical advise what can this be?

My car has 71457 miles.
My car has a manual transmission.

A: Hi, thanks for writing in. If you have cool...

Hi, thanks for writing in. If you have coolant in the engine oil showing on the oil cap, then you likely have a blown head gasket. The oil in the coolant is most likely from the blown head gasket getting compression into the coolant overheating the engine. I recommend having the vehicle checked by a mechanic to see if engine is repairable by replacing the head gasket and flushing the coolant and engine out. Here at YourMechanic, we can have a technician come to your home or office to inspect and diagnose this issue for you, and make or suggest the necessary repairs. Hope this helps and best of luck!

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