Fuel injectors are an invention that can improve automotive fuel economy and function within a car engine. However, they are precise instruments that can malfunction under use. When they do, they will cause all sorts of problems in how your car runs. However, these same problems are an easy-to-notice indicator that your fuel injectors are an issue and not something else.

Bad Idle or Complete Shutdown

One of the most common problems that signal plugged-up fuel injectors is horrible performance when the car is in idle. This problem won't happen suddenly; it will build up over time as deposits begin to clog the fuel injector nozzle heads. The fuel injectors will work fine when the throttle is pressed and fuel is being forced through the injectors. However, the idle at a stop sign is the hardest time for the injectors to work while driving, and the time when they are most prone to plugging up momentarily. Enough of a plug-up and your car will die, forcing you to restart it again.

Bad Fuel Economy

Your car should generally get the mileage described by your car manufacturer per gallon of fuel. If you start to notice you're burning a lot of fuel for far less mileage then you used to get, the problem could be a malfunction in your injectors. Fuel injectors are designed to replace carburetors and maximize fuel efficiency via a computer measuring fuel/air mixture with sensors. When the sensors say the mixture is off, then they require more fuel through the injectors. But if your injectors are malfunctioning, they can let in far more fuel than needed, ergo the loss.

Hiccupping and Cutting Out

While in drive and in gear, your car could start to sputter and cut out if your fuel injectors are severely plugged up. Even though you are telling the car via the throttle to put on the gas, it's not going through the system when the injectors are plugged. This is a rare situation, since most times the dying out in idle is enough of a signal to get the fuel injectors checked. However, in some extreme cases it takes cutting out while driving to come to the same conclusion. One example could be under extreme cold. In this case the engine is working hard in idle to stay warm, so it doesn't die out obviously. However, the same deposits are building up and eventually kill the car performance altogether.

Misfiring

A misfire in an engine today due to fuel injector problems is not that common. With carburetors misfires happened frequently, but with injectors and computer sensors the probability is far less. The car computers tend to be far too accurate in their mixtures to allow significant misfires to occur. That said, it does happen, but it is more likely due to a bad spark plug than a fuel injector issue.

Wear and Tear

Eventual age and use will wear down fuel injectors. Remember, injectors are fine, precision instruments. However, fuel is a solvent and can eventually wear down precision openings and parts. This makes the injectors less precise over time, regardless of how well they are operated. Like all car parts, fuel injectors can last a long time when taken care of, but eventually they do need replacement.

Source:

AA1Car: Driveability Diagnosis: Engine Misfires

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