What causes a rough idle when the engine is cold?
What causes a rough idle when the engine is cold? The cold-start injector is in charge of smoothing out a rough idle when the engine is operating at a temperature that is below optimal levels. One the engine reaches the right temperature, the cold-start injector turns off. If the injector is dirty or you are dealing with a bad fuel injector, it will not give the extra fuel needed. How can you tell if your car has a rough idle? Share it! It's easy to tell when your car has a rough idle: When you start the engine, it won't...