Does Your Car Starts Rough Then Smooths Out?

Does Your Car Starts Rough Then Smooths Out?

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You must have heard about the thing about first impressions, they create a major impact. The first impression is actually the last. If your car starts rough on the ignition, it is an embarrassing situation that degrades the quality of your vehicle’s first impression in front of anyone. Your car might even smooth out after starting rough but, that doesn’t mean that you can ignore this problem. Ignoring a rough idling stage can lead to a major problem in the future which is much more complex to repair.

If you are facing a situation in which your car starts rough then smooths out, there is a pretty good probability that the problem is not complex in nature. Such a scenario may occur due to many usual malfunctions in your running machine. This article will guide you through diagnosing the issue and some recommended fixes to get rid of the rough idling interval.

Why Does Your Car Start In A Rough Manner?

There can be various reasons behind this problem and these are really common in nature. These basic problems can be a reason behind the rough start of your car drive.

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1. Faulty Spark Plugs

Spark plugs function to provide the electric current for the ignition of air and fuel mixture in the combustion cylinder. The ignition process is powered electrically by spark plugs. Spark plugs channel the current from the ignition coil. Therefore, a faulty spark plug or spark wire is a potential reason for your fuel-burning at an inconsistent rate. This leads to a rough start for your machine when you provide ignition to it.

2. Moisture In The Ignition System

The ignition system is the mechanism that generates the heat required to burn the air and fuel mixture for getting your vehicle running. A layer of Moisture might form over the ignition system if it is exposed to water or dust. Henceforth, an ignition system with moisture over it causes inconsistent ignition. This can be the problem if your car starts rough then smooths out.

3. Leaking Vacuum

Modern cars have a throttle system installed in them. This system regulates the flow of air and uses a vacuum to control the engine speed. A throttle system uses a complex structure of hoses to create the required amount of vacuum. Normal wear and tear in these hoses can create a vacuum leak in the system. This unutilized vacuum makes your car experience a rough start.

4. Dirt In Fuel Injectors

Fuel injectors are a major component of your car’s ignition system. They function to inject the appropriate amount of fuel into the engine to ensure efficiency in the fuel-burning process. They also regulate the amount of fuel entering the car’s engine. It doesn’t matter whether the fuel entering into the engine is excessive in quantity or lower than the required quantity, both situations will cause a rough start for your machine. A dirty fuel injector hampers the complete process of fuel injection into the engine.

What To Do If Your Car Starts Rough Then Smooths Out?

There are a few easy fixes and repairs which you can try if you feel that your car starts rough and then smooths out. Some of these fixes involve cleaning a few specific parts, while the other solutions involve repair or replacement of a specific part or system.

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Fixes Involving Cleaning

If you are facing a situation where external factors like dust and moisture are degrading your car’s components, cleaning a particular part might help.

1. Getting Rid of Moisture From The Ignition System

The layer of moisture forming over the ignition system can be removed with the help of air blowers. Therefore, If you can diagnose a problem of moisture in the ignition system, cleaning it will help your car in achieving a smooth start.

2. Removing Dirt From Fuel Injectors

Dirt in the fuel injectors can be observed easily and removed with the help of injector cleaner gas. The injector cleaner gas removes all the dust particles and any other obstruction which causes inefficiency in fuel injection to the engine. A clean fuel injector will ensure proper combustion of the air and fuel mixture. Henceforth, clean fuel injectors facilitate a smooth start during ignition.


3. Cleaning Spark Plugs

Spark plugs are amongst the easily removable units of your car. A spray of compressed air will help you get rid of any dust particle or a layer of rust over the plug. A clean spark plug promotes the proper flow of current and the ignition process is completed without any obstructions. With a little knowledge about your car’s structure, you can clean the spark plugs yourself.

Fixes Involving Repair/Replacement

Cleaning is an easy solution for a problem that is basic in nature. Therefore, cleaning a part might not work if the damage is complex. Getting your ignition system checked by a professional is the best thing to do in such a case.

1. Repairing The EGR Valve

This valve helps in channelizing exhaust gases into the engine to achieve low engine temperature in specific situations. If this valve gets loose, it might release gases at the time of combustion, which causes a rough start. If your car starts rough then smooths out, it might be due to a leak in the EGR valve.

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2. Replacing The Spark Plugs

Spark plugs are some of the most frequently replaced parts of your car. If a spark plug is old and damaged, replacing it is a better option than just cleaning it. The replacement cost of a spark plug is nominal and the results are tremendously good. New spark plugs will help your ignition system to start smoothly.

3. Replacing The Ignition System

The ignition system generates a spark that provides heat to burn the fuel and air mixture. A faulty ignition system means a degraded standard of fuel efficiency and it adds up to the cost of maintenance for your machine. Replacing the ignition system is a good choice. Firstly, it will resolve the rough start and secondly, it will make your vehicle even more fuel-efficient.

What Is The Cost Of Replacement?

In some cases, a replacement of any specific part of your car might be the only option available to you. A new spark plug ranges between $15 to $100, depending upon the car’s specifications. A replacement of the complete ignition system of your car will cost you something between $200 to $400. Furthermore, a labor cost of around $100 should be considered.


The complete driving experience of your car is defined by how your car starts. A silent and smooth start inculcates a feeling of safety and comfort in the mind of the driver. Whereas, if your car starts rough then smooths out, it will provide a sense of discomfort. A bumpy start for your drive is something that should not be ignored.

Stay safe and keep driving

Thank you.