Truck Shaking, Spark Plugs, Engine misfiresHave you recently noticed your Ford truck shaking when idling at a red light? Maybe it started out as a small thing, but now it’s getting worse. Is it something you should get looked at? The short answer is, Yes! A shaking or rocking sensation from your truck’s engine compartment, plus engine misfires is an indication that a problem is brewing. It may be as simple as replacing your spark plugs, but it also may be more involved than that.

Below are several possible reasons that can make a vehicle shake while idling. Tracking down the true reason takes a dedicated, qualified technician with the experience and know how to get it fixed right. At Taylor Co Automotive Service, we always use the best parts, state-of-the-art diagnostic equipment & tools, by technicians that are ASE trained and certified.

Truck Shaking Possible Causes

The Ignition System

Your Ford truck’s ignition system is made up of a bunch of components that must all work together in perfect unison. If there is a flaw in the system, a good spark will not happen, which causes your vehicle to misfire. The shaking occurs as your truck’s engine struggles to remain running while at idle. A few common causes within the ignition system are:

  • Engine Misfires
  • Faulty Spark Plugs
  • Bad Ignition Coil Packs

Let’s look at these common culprits one at a time.

Engine Misfires = More Than a Loud Noise

When your truck’s engine misfires, there may be more going on under the hood than you realize. There is a specific combination of an air/fuel mixture, plus a spark and compression needed to successfully run your vehicle’s engine. All of these components need to happen at the correct times, in the correct amounts to produce combustion. If even one of these components is out of sync or working improperly, your engine can misfire. Misfires result in your truck running rough, shaking while at idle and making that popping sound.

Faulty Spark Plugs = Poor Performance

As your spark plugs get worn out, the engine will lose power. You could notice a slower acceleration or hesitation when you step on the gas. Your truck may be giving you a rougher ride, which can include shaking when slowing down or when stopped at an idle. The check engine light is often triggered by faulty spark plugs.

Bad Ignition Coils = Reduced Fuel Economy

The ignition coil pack is another important component in the ignition system of your Ford truck. When they go bad, the symptoms can be very similar to faulty spark plugs. There will be a noticeable decrease in acceleration plus an increase in gas usage. Misfires may also become more frequent.

Worn Motor Mounts

Another possible (but less common) reason your truck may be shaking, is worn out or broken motor mounts. These are brackets with rubber centers that hold your engine secure. They also help insulate the vehicle from the normal vibrations that occur while your engine is running. When the mounts become compromised you may notice a thumping or clunking noise when you accelerate, drive over bumps in the road or brake hard. 

Worn Transmission Mounts

Your truck’s transmission also has mounts that insulate the vehicle from the normal vibrations of its use. If your transmission has worn or broken mounts, excess vibrations there could cause a chain reaction to your engine, increasing the strain and movement of your motor mounts. These excess vibrations can lead to shaking in the engine compartment.

Vacuum Leak

Vacuum leaks can be tricky to diagnose. Your truck’s engine creates a vacuum while running. If there is a compromise anywhere in the vacuum system, the result can be noticeable shaking while at idle. Check inside your engine compartment to see if you hear a hissing sound. If you do, you may have a leak in the vacuum system which should be diagnosed and repaired as soon as possible.

Truck shaking Diagnostics

If your Ford truck is having any of these issues, take some notes on the when, where, and how often it happens to help the technician narrow down the usual suspects. A glowing check engine light is actually helpful in this situation. Running a diagnostic for trouble codes may find the culprit quickly and get you back in your truck and on the road. 

Let us Help

If you don’t have any illuminated dash lights, don’t worry, we’ve got you covered. Taylor Co. Automotive has been operating in the same location since 1989. We take pride in what we do and stand behind our work – that’s why we offer our famous Taylor Co. Lifetime Warranty. Make your appointment with us today by calling (909) 316-6166 or visiting our online appointment page.