读者Dave Liu 问：Dear technician Mr. Lee, I recently bought a 2004 Honda Civic at 16,730 Kilometers, and I found out that the engine oil from the car is very dark black in coloration. My technician has informed me that the oil has just been changed and that the engine oil is very black because the car has not been used for a long duration of time. Furthermore, when I drive my car more often and the oil change on time the color will return back to normal and the technician has told me that the black coloration will not affect the car’s performance. Also he said that the Civic car is unable to change the original battery connector. I was wondering if both of these statements provided to me by my technician were true and if you were able to provide me with any other reasons as to why the engine coloration would be black.
Thank you for your time, your help will be greatly appreciated! Happy New year!
李进答：Hi Dave, All motor oil contains cleaning agent additive required by the API(American Petroleum Institute) and SAE (Society of Automotive Engineers).The motor oil should be clear and golden color when first changed. If you open a can or bottle of motor oil the color is clear and golden.
However, as the engine operates, the motor oil cleaning agent will continue to collect and neutralize the harmful chemical byproducts from the combustion within the engine, including soots, and other hydrocarbon compounds, which will cause the oil gradually change color and darken. As long as you change motor oil according to the car manufacturer’s requirement (usually for regular motor oil it is every six months or 6,000 miles whichever comes first, or for synthetic motor oil it is every 12 months or 12000 miles whichever comes first.)
Always change oil filter with every oil change, and stick to original OEM oil filter as much as you can, avoid cheap oil filter.
读者Henry问：李先生您好！我的车是2010年Toyota Venza V6。只开了大约5万英里。车速达到70英里或以上时方向盘会抖。当车速45英里以上时踩剎车也会抖。还有个毛病，在颠簸路面时，方向盘柱里面发出「格格」声。有人说是有个螺丝松了。要拧紧它就必须换安全气袋。
3) 方向盘的噪音需要检查方向盘柱Steering Column和前轮悬挂系统的连桿松动有关。请检查。