The Toyota Yaris is a subcompact car that has been on the market since 1999. The Yaris is a fuel-efficient vehicle and boasts an economical 1.5-litre, four-cylinder engine. Users often report engine problems while the engine is on and the vehicle is not in motion, otherwise known as idling.
When stopped at a red light or stop sign, drivers can encounter rough idling. This means that the vehicle is not idling smoothly. The car's revolutions per minute fluctuate, creating a jerky movement in the engine. The jerking movement may be observed in the feel of the accelerator or the entire vehicle.
Another common trouble with an idling Yaris occurs when accessories are on. Headlights, fog lights, air conditioning and heater use increase rough and uneasy idling.
When the vehicle is idling and the driver initially releases the brake, a rough jerking motion may be felt in the engine and noticed in the car's initial movements. The RPMs increase rapidly and then level off to normal levels.
The Yaris runs very lean because the engine is so small and efficient. This means the engine uses as little gasoline and oil as possible. In 2006, Toyota recalled many vehicles in the United States, including the Yaris, because of a faulty part. This defective part causes the vehicles to leak oil and stall out or turn off completely.