Symptoms Definition

WARNING: This page is about a different variant/trim than selected.

Backfire: Fuel ignites in the intake manifold or in the exhaust system, making a loud popping noise.
Cuts Out, Misses: A steady pulsation or jerking that follows engine speed. The exhaust has a steady spitting sound.
Detonation/Spark Knock: A mild to severe ping which usually gets worse while under load. The engine makes sharp metallic knocks that change with throttle opening.
Dieseling, Run-On: The engine continues to run after the vehicle is turned OFF.
Engine Control Module (ECM) Commanded Reduced Engine Power: The ECM illuminates the Reduced Engine Power lamp and will limit engine power under potential engine damaging or emissions related conditions. A DTC may be not be set.
Fuel Odor: A noticeable smell of unburned fuel.
Hard Start: Engine does not start for a long time. The engine does eventually run or may start but immediately stall.
Poor Fuel Economy: Fuel economy, as measured by an actual road test, is noticeably lower than expected. Also, the fuel economy is noticeably lower than it was on this vehicle at one time, as previously shown by an actual road test.
Rough, Unstable Idle and/or Stalling: The engine runs unevenly. If severe, the engine or the vehicle may shake and the engine may stall.