Back to all

Idle Talk about Engines (Causes of Rough Engine Idling)

January 23, 2022

When you slow down at stoplight, your vehicle's idle should be smooth as silk.  But what happens when the engine is missing or idling roughly? That's your engine's way of telling you, "Hey, I've got something wrong with me and if you don't get someone to find out what it is, I may not start the next time you turn the key."

You can help your service facility if you can describe the problem in detail.  Here's a list of things to make a note of:

  • When is the problem happening, when the engine is cold or when it's been running for a while?
  • Does the rough idling occur when I'm accelerating or when I'm going at a steady speed?
  • Does it happen at high speeds?  Does it happen low speeds? Does it happen at both?

Make sure you describe the problem in as much detail because it will help a technician diagnose the problem.

One of the first things they'll check is how the spark plugs are firing.  Modern iridium plugs are supposed to last a long, long time.  But they CAN eventually wear out.  Inspecting the firing end can help the technician figure out the root of the problem.  Corroded or worn out spark plug wires, too, can contribute to an idling irregularity. 

There are other potential problem spots, too.  The technician may check the ignition coil, timing piston rings, valves and cylinder walls. 

If the mixture of air and fuel isn't correct, that may affect how smooth your vehicle is running.  Your service facility is equipped with diagnostic equipment that helps them pinpoint the problem.  Once that idle is smoothed out to the way it used to be, you'll be the smoothest operator on the road.

Tuffy Tire & Auto Service Aurora
3190 N. Aurora Rd.
Aurora, Illinois 60502
630-898-6688

More articles from Tuffy Aurora

Read a Good Tire Lately? (Tire Wear)

March 30, 2025

There's lots of good information to read in books and online. You might not know that you can also "read" your tires and learn a lot about what shape they're in and if they are in need of attention. It's important to know how your tires are doing because a tire failure can be very dangerous to y... More

Clean Machine (Fuel and Air Induction Cleaning)

March 23, 2025

As your vehicle ages, its performance isnt quite what it used to be, but many of us never notice the change because its gradual. So here are a few questions to ask yourself. Does your vehicle feel like it doesnt have the pep that it used to? Have you noticed your fuel economy isnt quite as good... More

Motor Oil?The Synthetic Advantage (Synthetic oil vs Conventional)

March 16, 2025

Youve probably already heard that regular oil changes are extremely important for the health of your vehicles engine. Thats sound advice. But what you might not know is when it comes to motor oil, the real thing may not be the best thing for your engine. There are different types of motor oil: ... More