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What causes rough idle at low RPM

What causes rough idle at low RPM - Most likely the cause of rough engine idle at low RPM comes from basic functional components such as direct fuel injection.

What causes rough idle at low RPM

This is because rough idle when the engine has been running for a while can be caused by one faulty component or through a series of other problems. However, it is easy to spot the problem, because during rough idle the engine will spin at an irregular speed or may have varying RPM values ​​without hitting the gas. The hot engine we mean here is not an overheated engine, but an engine that has finished warming up. And of course the two are very different.

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Now, to fix the rough idle issue at low RPM requires a sequential check of the components and then, the actual troubleshooting.

1. Collect Error Component Data

First, if your car has a universal scanner jack installed, fasten the code scanner and gather information about the faulty system component.

2. Component Analysis

With the transmission in parked or in neutral, make sure you apply the emergency brake as well. Next, check all components to find out the real cause of rough idle

3. Check and Replace Spark Plugs and Wires (if needed)

When the engine heats up, make sure it disables the choke connection. Then, using insulated spark plug wire pliers, take the spark plug wires from the attached location one by one in turn.

If during the process the engine speed does not go down, it clearly indicates there is a problem with the spark plug or spark plug wire. Mark on the spark plug wire (spark plug) what number when unplugged the engine speed does not go down.

Once a problem is detected with the spark plugs or spark plug wires, stop the engine and use the socket to remove each spark plug. Next, check the condition of the spark plugs. If any component is white or dark brown or looks wet, replace it immediately. Actually, check the correct gap between the plugs, refer to the service manual and use a measuring tool. Then reinstall all spark plugs and spark plug wires and start the engine. However, if not, then further investigation is required. 

4. Check the PCV Valve

Fix it by repairing components then, make sure everything is working and clean.

5. Check EGR Valve

A faulty EGR will make the engine indicator light come on, so that pointing towards the culprit is revealed by the code reader. The EGR valve can be cleaned or replaced.

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6. Check Air Filter

The filter housing requires cleaning of accumulated dirt. If the filter has damaged dirt, consider replacing it.

7. Check Oxygen Sensor

Digital multimeters and code readers can be used to identify the exact problem, and if the sensor fails, someone can easily replace it.

8. Vacuum Leakage Analysis

If there is a hissing sound from the hood, immediately check for the source of the problem. Here, if the engine indicator light comes on, with a lean-mixture trouble code on the engine computer, check for leaking components and replace them.

9. Direct Fuel Injector Test

If the direct fuel injector has a problem, clean it using a mixture of strong solvent and high pressure. Other options to try include fuel system additives, which clean the fuel injectors. 

Conclusion :

When the car idles roughly at low RPM it is difficult to understand the associated causes. This is because rough idle when warm/hot can be caused by a faulty component or through a series of problems.