What does the engine oil color tell you?
To know the engine condition, evidently could be detected through the color of the engine oil. The change in the color of engine oil could determine whether the component inside was still healthy or already have much damage. Engine oil color observation could give us a preliminary diagnostic of the engine condition.
Yellow (clear and transparent)
This is a new oil color, or new oil pouring to the engine. The engine has not start yet or just start for short time.
The engine had been used to go. The condition was still being considered to be normal, probably the car have been used for 1.000-2.000 km. Did not need the change.
Engine oil was black as a result of the car has gone around 3.000-4.000 km. Better be replaced with that was new when the interval have been reach, maximal the use normally around 5.000 km up to 10,000 km (depend on engine oil specification) . More than that, interval the engine temperature could be raised due to poor oil quality and as a result could damage the engine component. If the engine oil became black only after few weeks or short distance, it could be a problem inside the engine. The problems might be caused by amount of sludge especially for vehicles that use for more than 5 years. Engine flushing is recommended for this type of problems.
This color indicated that the engine oil was mixed with oil sludge and metal component as result of engine component friction. It is a danger warning sign, the engine component and lining probably have been worn. Try to change the oil immediately, if the results still the same, inspect the engine interior component, probably needs an overhaul.
This is resulting from oil mixed with water. It can be happen for several causes i.e:
Leaking top head gasket
Leaking/damage oil cooler
Or improper oil filter installation
This milky brown color is a serious warning indication. Do not start the car (can cause a water hammer), drain all fluid (oil and coolant) from the engine immediately. Late action can cause rust developed inside the engine. See my previous posting about water inside the engine.
So, what are you waiting for? Check your engine oil color.