Rough idle

A common cause – and also an easy one to fix – is a loose or broken vacuum hose. They can wear easily over time, but by looking in the engine compartment you should be able to see if there are signs of abrasion, breaking or loosening. Modern cars use sophisticated fuel injection systems to meter fuel, which relies on a vacuum to help the engine’s computer determine the precise engine condition. If not working properly it can cause serious engine damage. Rough idling can also be caused by clogged filters. It’s hard to tell if a filter is clogged, so it’s best to replace at each tune-up. An air filter cleans the air entering the engine and prevents debris from entering the engine and causing damage. As the capacity to filter the air going into the engine is reduced, the engine is not able to function properly. There could also be something wrong with the vehicles’ electrical components. Bad spark plugs, bad spark plug wires and a bad distributor cap are other common causes of rough idling. These items are all important parts of what keeps a vehicle running. Spark plugs provide the spark that ignites the air and fuel mixture within the cylinders. This continuous ignition is what keeps a car moving down the road. A distributor cap regulates the firing order of your vehicle’s engine.

Loose/broken vacuum lines ? are the injectors firing normal ? scan for codes even if the light ain't on