Signs of a fuel injection problem include inconsistent engine power and engine misfires. Fuel unable to consistently move to the engine can cause the engine to fluctuate between revving high and low or misfiring. A misfire could trigger a misfire code and the Check Engine light.
A fuel injector that is clogged or dirty may cause rough idling. Sometimes fuel injection problems are the result of a leak in the injector or in the lines from the injector to the engine. In such cases, there may be a strong smell of gasoline inside and outside of the vehicle, reduced gas mileage, and difficulty starting the engine.