What gases are produced when engine oil burns?

[LaAyla]

Engine oil burning produces carbon monoxide. Introduction to Engine Oil: Engine oil, also known as engine lubricant (English name: Engine oil), serves multiple functions for an engine including lubrication and friction reduction, auxiliary cooling, sealing against leaks, rust and corrosion prevention, as well as shock absorption. It is often referred to as the "blood" of a car. The base oil is the primary component of lubricating oil, determining its fundamental properties. Additives are used to compensate for and improve any deficiencies in the base oil's performance, imparting new characteristics, making them an essential part of lubricating oil. Composition: Engine oil consists of two main parts: base oil and additives.

[StColin]

Last time my neighbor's vintage car was burning oil, the mechanic chatted with me about it. Engine oil is mainly composed of hydrocarbons, which turn into water vapor and carbon dioxide when burned, but it's worse if the car's condition is poor. Incomplete combustion produces carbon monoxide, which is toxic and can easily cause dizziness with the windows closed. There are also black carbon particles, with blue smoke coming out of the exhaust pipe, covering the rear window with soot. The most annoying part is nitrogen oxides, which react with sunlight to form ozone, making it very pungent. If the engine oil contains metal additives like lead or zinc, burning them releases even more toxic substances, smelling like rotten eggs. So if you notice blue smoke from your car, get it fixed immediately—it not only wastes fuel but also harms your lungs.

[AliyahDella]

My decade-old SUV started burning oil last year, and the exhaust became particularly pungent. A mechanic friend explained that normal oil combustion should produce colorless water vapor and carbon dioxide, but incomplete combustion in older vehicles leads to odors. The most common symptom is light blue smoke, primarily composed of unburned hydrocarbons, similar to smog components. The sticky residue on the exhaust pipe is acidic condensation from sulfur oxides. The most hazardous scenario is black smoke containing carbon monoxide, which tends to accumulate during idling in parking areas. I once felt dizzy in the garage due to this. The advice is to regularly inspect older vehicles and switch to better-quality engine oil to reduce pollution.

[VonLillian]

Studying chemistry involved researching motor oil composition, and the combustion byproducts are quite complex. Hydrocarbon combustion should ideally produce water and carbon dioxide, but in reality, it generates byproducts. Carbon particles are the main component of black smoke, contributing to particulate pollution. Sulfur-containing oils produce sulfur dioxide when burned, which smells like lit matches. At high temperatures, nitrogen reacts to form nitrogen oxides, which are irritating to the eyes and nose. The most troublesome are volatile organic compounds like benzene derivatives, which are major sources of carcinogens in exhaust. These gases combine to create the distinctive odor of vehicle exhaust, which is highly harmful to the respiratory system.