Car Shakes When Stopped, Check Engine Light On

Causes

There are several potential causes for a car to shake when stopped with the check engine light on, including:

Engine Misfire

A misfire occurs when one or more of the engine’s cylinders fails to properly ignite the air-fuel mixture. This can cause the engine to shake and run rough, especially at idle.

Vacuum Leak

A vacuum leak allows air to enter the engine’s intake system, which can lean out the air-fuel mixture and cause the engine to run lean. This can also lead to a shaking engine and a check engine light.

Faulty Ignition Coil

The ignition coil provides the spark that ignites the air-fuel mixture in each cylinder. If the ignition coil is faulty, it can cause a misfire and a shaking engine.

Bad Spark Plugs

Spark plugs are responsible for providing the spark that ignites the air-fuel mixture. If the spark plugs are worn out or dirty, they can cause a misfire and a shaking engine.

Dirty Fuel Injectors

Fuel injectors spray fuel into the engine’s cylinders. If the fuel injectors are dirty, they can restrict the flow of fuel, which can cause a misfire and a shaking engine.

Clogged Catalytic Converter

The catalytic converter helps to reduce emissions by converting harmful pollutants into less harmful substances. If the catalytic converter is clogged, it can restrict the flow of exhaust gases, which can cause the engine to shake and run rough.

Low or Dirty Engine Oil

Engine oil lubricates the engine’s moving parts and helps to keep it running smoothly. If the engine oil is low or dirty, it can cause the engine to overheat and shake.

Diagnosis

To diagnose the cause of a car shaking when stopped with the check engine light on, a mechanic will typically begin by reading the trouble codes stored in the engine’s computer. These codes can help to identify the specific problem that is causing the shaking. The mechanic will then perform a physical inspection of the engine and its components to look for any signs of damage or wear.

Repair

The repair for a car shaking when stopped with the check engine light on will depend on the underlying cause. In some cases, the problem can be resolved by simply replacing a few spark plugs or cleaning the fuel injectors. In other cases, more extensive repairs may be necessary, such as replacing the ignition coil or catalytic converter.

Prevention

There are a few things you can do to help prevent your car from shaking when stopped with the check engine light on, including:

* Keep up with regular maintenance, such as oil changes and tune-ups.
* Use high-quality fuel and oil.
* Avoid driving your car if the check engine light is on.
* Have your car inspected by a mechanic if you notice any unusual shaking or vibrations.

By following these tips, you can help to keep your car running smoothly and avoid costly repairs.