A Brief History of Carbon Removal
Automotive technology is rapidly changing and so must induction cleaning systems. Cleaning methods are outdated because they were not specifically designed to deliver cleaning chemistries into the modern automotive engine. Additionally cleaning chemistries are outdated because modern fuels and oils have been re-engineered thus altering the chemical nature of the carbon deposit. Virtually all off-the-shelf products were designed based on their ability to remove laboratory produced Rapid Carbon Accumulation (“RCA”) carbon instead of real types of carbon deposits that form in every day real-world vehicles. This Industry standardized carbon deposit uses a special fuel base that is never actually used for road driving. The purpose of RCA is to generate the same carbon thickness and carbon volume in 5,000 miles, based on the use of dynamometer testing (not on road operation) that a road vehicle engine will generate in 100,000 miles of actual driving. Therefore the structure of the carbon deposit generated in the RCA method is not the same as that generated in road vehicle engines. First, there is the difference in fuel; the special RCA fuel base vs the different commercially available fuels which vary with manufacturer, region of country where they are dispensed, and time of the year (in some states up to 10% of the gasoline is ethanol in winter months). The second difference is that in road use the carbon deposits are only partially created by the fuel, whereas the RCA carbon is mainly comprised of the fuel. In road vehicles a large amount of the induction system carbon deposit is created from the engine oil that is taken in through the Positive Crankcase Ventilation (“PCV”) system. Additionally, the Exhaust Gas Recirculation (“EGR”) system (whether external of internal) allows burned exhaust gases to re-enter the induction system, further contributing to the carbon deposit composition within the induction system. The PCV and the EGR contributed carbon deposits will take many thousands of road miles to accumulate within the induction system. These types of carbon deposits are not typically generated via RCA. Yet another difference between RCA carbon deposits and road vehicle carbon deposits is that RCA carbon deposits do not have the same thermal soak cycles or soak times as a high mileage road vehicle would have.
Once a test engine has been run under controlled laboratory conditions with the RCA fuel and has enough carbon build up, a mixture of known chemicals (i.e.,a solution) is then formulated to remove or try to remove these RCA carbon deposits. Thus, even if the developed solution can remove at least some of the RCA carbon deposit, it may not work to effectively remove real world carbon deposits.