Hello there, I'm Kimi, your go-to expert for automotive and mechanical issues. With a background in engineering and a passion for all things mechanical, I've spent countless hours diagnosing and solving problems just like the one you're facing.

A rough idle at low RPM can be quite frustrating, and it's often a sign that something isn't quite right with your vehicle's engine. There are several potential causes for this issue, and I'll walk you through some of the most common ones, as well as some less obvious culprits.

1. Ignition System Issues: The ignition system is responsible for igniting the air-fuel mixture in the engine's cylinders. If there's an issue with any component of this system, such as the spark plugs, ignition coils, or ignition wires, it can lead to a rough idle. Dirty or faulty spark plugs can cause misfires, which can make the engine run roughly.

2. Fuel System Problems: The fuel system delivers fuel to the engine. If there's a problem with the fuel injectors, fuel pump, or fuel filter, it can affect the engine's performance. A clogged fuel filter or failing fuel pump can starve the engine of the fuel it needs, leading to a rough idle.

3. Air Intake and Throttle Body: The air intake system brings air into the engine. If the air filter is dirty or the throttle body is dirty or malfunctioning, it can restrict airflow and cause a rough idle. Loose or disconnected air/vacuum hoses can also cause vibrations and a rough idle due to improper air-fuel mixture.

4. Engine Timing: The timing of the engine refers to the synchronization of the pistons' movement with the opening and closing of the valves. If the timing is off, it can cause a rough idle. This can be due to a worn timing belt or chain, or issues with the camshaft or crankshaft sensors.

5. Vacuum Leaks: Vacuum leaks occur when there is a breach in the engine's vacuum system. This can cause an improper air-fuel mixture, leading to a rough idle. The loose or disconnected air/vacuum hoses mentioned can be a source of vacuum leaks.

6. Engine Mounts: The engine mounts, or motor mounts, are what hold the engine in place within the vehicle. If these mounts are broken, they can cause the engine to move excessively, leading to vibrations and a rough idle.

7. Exhaust System Issues: Problems with the exhaust system, such as a clogged catalytic converter, can also lead to a rough idle. The exhaust system is responsible for expelling the burnt gases from the engine, and a blockage can affect engine performance.

8. Sensor Failures: Modern engines rely on various sensors to monitor and adjust engine performance. If a sensor like the mass air flow sensor, oxygen sensor, or throttle position sensor fails, it can cause a rough idle.

9. Engine Mechanical Issues: Internal engine problems, such as worn or damaged piston rings, can cause a rough idle. These issues can lead to compression losses and affect how the engine runs.

10. ECU/PCM Problems: The engine control unit (ECU) or powertrain control module (PCM) is the brain of the engine. If there's a problem with the ECU/PCM, it can cause a variety of issues, including a rough idle.

Diagnosing a rough idle can be a process of elimination, starting with the most common and easiest to check items, and then moving on to more complex and less likely causes. It's important to use a systematic approach to identify the root cause of the problem.

Now, let's move on to the translation.

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Loose or disconnected air/vacuum hoses can cause vibrations too. Dirty or faulty spark plugs make the engine, or at least some, cylinders misfire which has as a result engine vibrations. Or the most likely cause of all broken motor or transmission mounts.read more >>