Car manufacturers have long praised the advantages of fuel injection, claiming increased efficiency and power. But as more cars have installed the system (around 73% in 2023), more and more consumers are dealing with a problematic and relatively current side effect of the system after also little as 20,000 miles on the road: carbon accumulation on engine intake valves.
After having undergone tests and racing tests, mainly by Mercedes in the 1950s, the capacity of the system to Improve power was well established, and it was only a matter of time before being widely adopted on road cars. At the beginning, most of the injection systems placed the injector over the intake valve, leaving the fuel / air mixture sprayed on this valve, then falling into the combustion chamber once the valve has opened, more commonly called port injection for the way the steam was sprayed in the port of intake. This solution is cheaper, simpler and allows fuel a little additional time to spray and mix with air to maximize combustion at critical moment.
Fuel injection directly into the combustion chamber, however, allows the engine to use a higher compression ratio without fear of early detonation because the fuel acts really to cool the room. This can lead to a serious increase in power, a test finding a difference of 65 horsepower between the port and the direct injection.
Disadvantages of direct injection
It was not until 2004 that direct injection made its way to a mass -produced petrol car (diesels have always had a direct injection) with the Audi A6. And although this car has taken advantage of the advantages promised by direct injection, carbon accumulation is now among the most common problems encountered by these engines. Carbon deposits are the result of incomplete combustion, a reality of any fuel combustion engine. A more cleaning burning engine Quality essence use can help reduce the problemBut the accumulation is inevitable.
Port injection systems can mitigate these problems because the fuel mixture washes the intake valve while it flows from the intake port to the combustion chambers, but direct systems jump this step and therefore do not have a system of autonomy. But there are a lot of products, and even certain decisions that manufacturers can make, to mitigate these problems.
Some car manufacturers have decided to use both port and direct injection on each cylinder. Toyota has a system that uses both port injectors and direct injectors when less energy is required from the engine, while direct injectors take over because the engine is invited to produce more energy.
So what can you do?
There are a few things that a driver can do to mitigate or even clean the carbon that has been able to develop during the life of the engine. To avoid problems, Some recommend oil capture cans To capture any oil or non -burned gas which has exceeded the rings so that the mixture rich in carbon is not allowed to settle on the valves. You can also try to avoid these short races to grocery store, which can also worsen carbon accumulation As the engine deliberately manages the fuel rich in fuel to warm up, and all this additional fuel is unlikely to be burned in combustion.
A more entertaining solution could be to use your engine for its full range of Rev. The excess heat of Run to Redline can help To break the deposits.
There are also a lot of fuel additives whose aim is to help avoid these accumulations or break those that have already formed. Injectors of a direct injection system are also sensitive, especially for cars that are mainly used for short journeys. And, of course, in the worst cases, the engine can be disassembled and individual parts with direct treatment, but it is not necessary in the vast majority of cases.
