Back to all

Idle Talk about Engines (Causes of Rough Engine Idling)

April 17, 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.

South Side Garage
9117 S WALKER AVE
OKLAHOMA CITY, Oklahoma 73139
405-308-1514
http://www.thesouthsidegarage.com

More articles from Southside Garage

Restore Your Get-Up-and-Go (Fuel and Air Induction Cleaning)

December 14, 2025

You may have heard the old saying, "My get-up-and-go got up and went." If your vehicle's engine's fuel economy is noticeably worse, your engine is idling roughly or stalling or your vehicle's acceleration isn't what it used to be, ask your service advisor if you might need your vehicle's fuel and... More

Snake in the Engine (Serpentine Belt)

December 7, 2025

There's a belt that snakes through your engine. It's even named for a snake, the serpentine belt. It'll bite you when it breaks, possibly leaving you stranded. So, it's good to know a little about this snake-like belt. In early engines, there were lots of belts. They were used to convert the r... More

Catalytic Converter Replacement

November 30, 2025

Many of us have become aware of how important it is to keep our planets air clean, and your vehicle has a key component that helps do just that: the catalytic converter. Its in the exhaust system, and its job is to superheat unburned, harmful byproducts in the exhaust, so they dont get spewed ou... More