Blog

With a new day, I am here with another common problem many vehicle owners face these days: car idles rough but drives smooth? or car sputters when idling? It can be quite irritating that after a long tiresome day when you start your car to go back home you find your neutral car hard to operate. This problem mainly occurs after your car has travelled 500,000+ miles on an average. But can you identify rough idling? What causes this problem to arise? How can you fix it? Don’t worry, I got you!

Reasons Behind Car Idles Rough But Drives Smooth:

While there can be a number of both major and minor issue(s) but some reasons can be more prominent than the others. Below are a few such reasons which may be the culprit of your inconvenience caused:

1. Loose parts

If your car has crossed a milestone of 500,000 miles, it is not uncommon to observe loose parts and it can be the reason behind rough idling.

2. Vacuum Escape

Under the hood of your car, you can spot a considerable number of hoses and pipes. These pipes are responsible for fuel and air transporting from one part to another. Over a long time, these pipes go extensive wear and tear. In such a case, vacuum leaks are pretty common. Thus car idles rough but drives smooth.

3. Debris

If any debris gets stuck inside important fuel pipes, they can choke the proper flow of fuel thus putting excessive stress on the passing canal and a scarce amount of fuel can reach the ignition area. It can even lead to poor mileage.

4. Rusted Fuel Injectors

It may be possible that your car’s fuel injectors have worn out beyond repair. It is relatively a common issue every car owner faces after some time and can be cured easily. You just need to throw away the old ones and get new injections installed.

5. Faulty Spark Plugs

Being under continuous stress in running condition spark plugs or plug wires are bound to get worn out. Improperly installed or damaged sparks plug may lead to inconsistent and out of step fuel burning.

6. Damaged electrical Parts

Many major parts of your car run on electrical connections like ignition etc. In case it is faulty, you may experience car idles rough but drives smooth

7. Sensors Are Expired

A system consists of many sensors like the airflow sensor or oxygen sensor etc. These are read frequently by the car engine’s computer to determine many major decisions like the amount of fuel needed to release in the engine. Along with the check engine, car light idles rough but drives smooth.

How Do You Smooth Out Rough Idle?

Depending from person to person, one may prefer professional help while another may not mind getting his hands dirty at all. While former may not have a good impact on your pocket nut it can prove to be beneficial for your suspension in the long term. On the other hand, latter can not only help you save a few bucks but can bless your suspension with a good life too if not compromised on quality.

But some commit the blunder of using cheap products and have to pay exponentially later for the extra damage caused. To save you from this regret, here are a few suggestions which might help you:

1. Change Damaged Parts

Make a habit of replacing the damaged parts as soon as possible otherwise, the damage may extend to further parts in no time. Change your car’s whole interior mechanism for every 500,000 miles travelled.

2. Find A Professional Code Scanner

Take your vehicle to a nearby reputed garage where code scanner is available. They will plug in a code scanner and retrieve all the data from the car’s computer and check for faults.

3. Keep Spares Ready

It is a responsibility of every car owner to always keep a few necessary spare parts handy. It is a sign of a good owner.

4. Replace Rusted Parts

Bid good-bye to those primitive rusted models and gift your car a few brand new modern parts and watch your car’s performance doing wonders!

5. Carburettor Cleaner

IF you notice car sputters when idling or the exhaust smoke coming out of your vehicle to be black, it indicates poorly performing carburettor.  Add a carburettor cleaner to keep clear of debris and smooth running of the vehicle.

6. Change Sparks Plug

Quite an easy job is to replace worn-out spark plugs with a new one.

7. Check The Hoses

As mentioned above, check for malfunction of hoses and pipes. If faulty, get their replacements from any nearby hardware store and repair it.

8. Avoid High-End And Low-End Garages

For your car repair, do not trust on low-grade repair stores. Always keep a keen eye on quality. But also avoid going to costlier ones too as they may dig a big hole in your pocket. It is better to go to a certified mechanic and getting it done for the most benefit.

9. Fix Leaks

Once you find the faulty leak, take it to your nearby garage and correct it.

Frequently Asked Question Related to Car Idles Rough But Drives Smooth:

What Causes a Rough Idle on a Car?

Spark Plugs. A rough idling engine can be caused by spark plugs or spark plug wires. Spark plugs use the electrical current received from ignition coils to ignite the air/fuel mixture within the combustion chamber.

Should Idling Be Smooth at Low Rpms?

Idling should be smooth at low RPMs, but unfortunately the slightest problem with your car engine will first appear at idle.

Can a Vacuum Leak Cause a Rough Idle?

If one gets a leak, it causes a lean air/fuel mixture, which creates a rough idle. It can also turn into an engine misfire because of the combustion fault inside one or more cylinders. Vacuum leaks can also occur from leaking vacuum supply tanks, vacuum brake boosters and intake manifold gaskets.

How Do I Know If My Car Is Idling Properly?

You may also notice odd sounds, as well as inconsistent RPM counts. Normally, a vehicle should have a smooth and consistent RPM rate of around 1,000. If your vehicle is falling below or rising above this you may be dealing with an idling issue.

How Much Does It Cost To Fix Rough Idle?

While repairing cost is subjective and can vary from place to place and model to model. Although you may take professional help from the service centre, it may cost you exponentially. Undoubtedly quality and service will be of supreme quality.

On the contrary, taking the help of local downgrade mechanic may provide you with a quick fix and be budget-friendly but chances are it will increase damage in the near future due to low-quality material used. So it is better to take help of a certified expert in this field of damage rather than going for extremes.

A new valve will cost you anywhere between $150-$500 depending on quality. If you go to a verified service centre of the manufacturer it will easily cost you $450+. Additional labour cost ranges from $50-$100.

Is It Ok To Drive With A Bad Ignition Coil?

Yes, it is completely okay to drive your car with rough idling but for a short period. You should repair it soon or it may extend damage to another level. You do not want that to happen, do you?

If ignored it can adversely affect your car’s overall performance, fuel economy and potential engine problems shortly. It will also induce other side effects such as unwanted noise, car shaking etc.

Summing Up

So now you know the causes behind car idles rough but drives smooth. Not only this, but you can also even solve them now. After some time, it is a natural behaviour of your car to misbehave. Do not panic, take a few deep breaths, park your car at side and check for the symptoms. Hope you like today’s blog, for more queries let me know below in the comment section.

Thank you.

Happy driving!