Once you start your car, the gas needs to go to engine from the tank by fuel injector, and the fuel needs to go to engine from gas tank, and they burn in the engine and generate energy. The function of the fuel injector is to convert the liquid gas to a fine mist (spray) in order to make it burn easily. The number of the fuel injector is same as the number of cylinders for the engine in your car. So a good fuel injector allows your car to get superior gas mileage and boost extra horsepower and cleaner emission. As for fuel injector, here are some symptoms indicating your fuel injector goes wrong: if the Check Engine Light is on; if the engine misfire happens a lot; if you are suffering poor gas mileage; if you find there is a fuel leakage; if you smell the odor of gas. Don't wait a second and check your fuel injector right now. We are glad to offer you all General Motors genuine OEM fuel injector with a discounted price.