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

Rumble from Down Under (Muffler Replacement)

December 7, 2025

Weve all noticed them at one time or another on the street: a car or truck that drives by and the deep roar from their exhaust system sounds like a drag racer on the line. But what happens when that rumble is coming from under YOUR vehicle? Well, it could be a sign your muffler needs attention. ... More

(Ball Joint Replacement)

November 30, 2025

Every day that goes by, our bodies get a little more wear and tear on them. Our vehicles have the same issue. The older we get and the farther we travel, certain parts start showing some wear. Think of your hips. There are parts of our vehicles that are similar to them; just like hips allow y... More

Growing Old Together (Maintaining an Older Vehicle)

November 23, 2025

More and more of us are hanging on to our vehicles longer. A company by the name of HIS Markit recently released a report that shows the average age of light vehicles in the U.S. is now 11.8 years. Light vehicles are cars, SUVs (sport utility vehicles) and CUVs (compact utility vehicles). In C... More