* Ignition Coils: These deliver high voltage to the spark plugs. A faulty coil can prevent proper sparking in one or more cylinders, leading to misfires (the shaking) and triggering the check engine light.
* Worn or Damaged Ignition Wires (Spark Plug Wires): These transmit the high voltage from the coil to the spark plugs. Cracks or damage can cause weak sparks or misfires.
* Mass Airflow Sensor (MAF Sensor): This sensor measures the amount of air entering the engine. A dirty or faulty MAF sensor can cause a lean or rich fuel mixture, leading to rough running and the check engine light.
* Oxygen Sensors (O2 Sensors): These sensors monitor the exhaust gases to help regulate the air/fuel mixture. Faulty O2 sensors can lead to inaccurate fuel delivery and engine performance problems.
* Catalytic Converter: A clogged or failing catalytic converter can restrict exhaust flow, causing engine misfires and triggering the check engine light.
* Vacuum Leaks: Small leaks in vacuum lines can disrupt the engine's intake system, leading to irregular running.
* Fuel Injectors: A clogged or malfunctioning fuel injector can cause insufficient fuel delivery to one or more cylinders.
* PCV Valve (Positive Crankcase Ventilation): A faulty PCV valve can lead to excessive pressure build-up in the crankcase, affecting engine performance.
* Engine Mounts: While less likely to trigger the check engine light, worn engine mounts can cause excessive shaking.
What to Do Next:
1. Get the Diagnostic Trouble Codes (DTCs): The check engine light stores codes indicating the problem area. You can obtain these codes using an OBD-II scanner (available at most auto parts stores). These codes are crucial for pinpointing the issue.
2. Have the codes checked by a mechanic: Even with the codes, proper diagnosis can be complex. A mechanic can interpret the codes and perform further tests to determine the exact cause of the problem. Simply replacing parts based on guesses is inefficient and expensive.
Don't continue to drive the vehicle extensively with the check engine light on and shaking. This could cause further damage. Get it diagnosed promptly to avoid more significant and costly repairs.
