One of the most common mechanical problems in cars today is that their fuel injectors are dirty and clogged. When cars have faulty fuel injectors, they have trouble starting or run very erratically and unevenly. Some of them stop and reject before debugging. This is very common as cars get older and start to accumulate long miles, but it can also happen if you have a car that has been sitting for a long time.
Although the modern fuel injection system has changed the way car engines are started, there are some built-in design points in the system that must be observed and maintained to avoid problems. Today, the engine of almost every car starts when the ignition switch is turned to the on position.
When this happens, the fuel injectors spray
a fine mist of fuel into the intake manifold pipes, causing the fuel spray to vaporize immediately. This must happen because liquids cannot be used to power the engine, only the vapor produced burns. The spray from the nozzles should be a very fine mist. The lighter and finer the particles in this fog, the easier it is to turn into combustible vapors. If your engine has dirty fuel injectors, they will not be able to inject a fine, evenly distributed mist.
Sometimes the injectors just spray more fuel in one direction, or the spray may be a trickle or thick spray instead of the fine mist required. Fuel can also continuously come out of the nozzles if they are not completely closed.
If you have a car that refuses to start,
it could be due to fuel injectors that are stuck and won’t open at all. In cars that run rough and misfire, the problem may be an uneven air-fuel mixture in the cylinders. This means that some may get too much or too little of the fuel they need, and this causes problems in the overall combustion cycle.
A misfire in the cylinders means that the oxygen in them is not being used for combustion. Instead, oxygen is forced out of the tailpipe in the next exhaust stroke.
Today’s cars have computerized oxygen sensors that measure
and monitor this unused oxygen, and this causes the computer to react as if the engine is running very lean. What then happens is that the computer controlling the fuel injectors tries to compensate by adding fuel to all cylinders, keeping the injectors on longer.
This situation causes even cylinders receiving the correct amount of fuel to have too much fuel, making them too rich. Now the system that was supposed to correct the problem mistakenly overcorrected and made your engine run worse than before. It gets worse until you fix the original culprits which are dirty fuel injectors.
Since the fuel is supposed to be clean
and the vehicle’s fuel system has additional filters that collect dirt like dust and dirt particles, it seems hard to see how the injectors could get dirty. Conventional fuel filters are designed to trap particles between 10 and 30 microns in size.
To show what this size means, you should know that one micron is only one millionth of an inch. So you can see that these filters are trying to catch a lot of particles. They can even overload themselves, but usually they can keep most of the dirt out of the injection system. Liquids can carry very small impurities through the filter.
At slower engine speeds, not much fuel comes
through the fuel injectors, and sometimes very small particles and contaminants can get trapped in the tiny valves that release the spray. Drivers may find that a few revolutions of the engine with the foot pedal can wash these deposits away.
Another problem is that the sprays tend to stick or get dirty due to the residue that accumulates in the sprayers. When the engine is turned off, the fuel evaporates from the tip of the injectors. The tops of the nozzles are the first to undergo the evaporation process, leaving behind a sticky residue. You may be able to start and run the engine for a few minutes and wash off some of these deposits, but usually a little dry cleaning is your best bet. Motorists often notice that gas companies advertise fuel Rengøringshjælp additives in their products. Some fuels with more additives can run cleaner than conventional fuels. It also helps keep the injectors clean, but almost all gasoline products contain at least some of these clean fuel additives.