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Brown gunge on my oil cap...
I have a Mercedes car 200 Kompresser 05 year.The trouble is I was putting engine oil into lt there was some brown gunge on the cap can you please tell what it is.
Our answer:
Hi Pat,
It is usually caused by contaminated oil, often by moisture and sometimes, but not always, from coolant getting in because of a blown head gasket.
If you have any doubts, bring the car to a good mechanic to have a look.
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